Iwo Jima - Why Not Just Blockade It?
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- Опубліковано 27 сер 2024
- Many justifications for the invasion of Iwo Jima have been offered, some after the event. In this video we will take a closer look at whether it was absolutely necessary to invade Iwo Jima, or whether the Allies could have blockaded and gone around it.
Bibliography
“506th Fighter Group - Iwo to Japan.” 506th Fighter Group Iwo to Japan: 506th Fighter Group, 457 Fighter Squadron, 458 Fighter Squadron, 462 Fighter Squadron Iwo To Japan. Accessed October 1, 2022. www.506thfight....
Bradley, James, and Ron Powers. Flags of Our Fathers. New York, NY: Bantam Books, 2016.
Burrell, Robert S. “Breaking the Cycle of Iwo Jima Mythology: A Strategic Study of Operation Detachment.” The Journal of Military History 68, no. 4 (2004): 1143-86. doi.org/10.135....
Grimsley, Mark. “What If the Navy and Marine Corps Had Bypassed Iwo Jima?” World War II Magazine, December 2007.
Keegan, John. The Second World War. New York: Penguin, 2016.
Moskin, J. Robert. The U.S. Marine Corps Story. New York: McGraw-Hill, 1982.
Newcomb, Richard F. Iwo Jima. New York, NY: Bantam Book, 1979.
Pratt, William. “What Makes Iwo Jima Worth the Price.” Newsweek, April 2, 1945.
My grandfather was a radio operator on a b-29 flying out of Saipan, and on his return trip from a raid, one of his engines had been damaged and caught fire around Iwo Jima and they had to make an emergency landing on the little island. So I must say that at least I should be thankful that the allied command decided to take the little remote island.
Wait, was this during the battle for Iwo Jima? Because there was a bomber that came in with that exact situation that landed at one of our airfields, while the lines were off to the north.
@@michaelmikelson2946 how would he know your email
Why are you thankful? I guess you were not born yet at that moment. So, in case your grandfathers B-29 was lost en he was killed in action, you never had known him.
@@michaelmikelson2946 He has nothing because he made that up.
@@michaelmikelson2946 I have a ton of emails an about 24 gigs of footage from when my grand pa was there, he landed in the first wave,
The iwo jima saga between this channel in collaboration with The Operations Report has been absolutely brilliant
Bringing history to life.
Agreed! Amazing work!
"in collaboration" it's the same dude X')
In parallel maybe? In collaboration sounds wrong.
Well said. You beat me to it.
Nah! we should make more war! let more american come in! and then we can destroy them one by one!
Little known fact: Iwo Jima is included in the Greater Tokyo Metropolitan Jurisdiction so its capture meant that a portion of the nation’s capital fell to enemy hands. This is the reason why Japan was prepared to fight bitterly for it because not only its Japanese lands, it’s part of its nation capital.
It was the first piece of Japanese soil we captured. That alone made it valuable. It wasn't just taking back a war conquest like the Soloman Islands or taking a colonial possession like Saipan.
@@koharumi1What do you mean?
@Koharumi *America with the support of it's allies
Yeah, it doesn't, but I don't get your point.
@@AdamantLightLP ok i figured it was a typo
@@lawv804 we?
What did you do, fat boy?
I feel as though trying to weigh the pros and cons of the invasion a bit difficult to really discuss with Iwo Jima. It is clear from all of the changes to the bombardments and planning of the invasion that the amount of casualties were very unexpected. It was unknown how well the defenders had prepared and changed their engagement doctrine to make the American forces pay. Even if the end results might not have outweighed the losses, it was not something they had imagined for the invasion.
Tarawa on the other hand, piece of cake!
Only 3,000 US casualties.
Bad planning.
Nah! we should make more war! let more americolors come in! and then we can destroy them one by one!
Great planning btw.
"We know how hard the Japanese fight, and how well they can entrench given a bit of time, but we're going to assume that they're not gonna bother to make much of an effort defending this strategically vital island they have been on for 20 years."
(Must be the ancestors of the same people who today make the assertion that an invasion of mainland Japan would have cost 20-30 thousand lives max.)
A longer pre-invasion softening up bombardment and more shells in bombs on delay fuses! there was next to no intelligence evidently! they would not have been bogged down on the beaches if they had been apprised of the conditions of the time of sand.
It's amazing how the Japanese defended the island against all odds. If other Japanese Generals or Officers think & act like General Kobayashi, US casualties in Pacific might have been quite high. The senseless Banzi charges and Harakiri suicides did the trick in lowering US casualties.
Peleliu........ That invasion was a bureaucratic machine set into motion that was a Complete waste of Lives, Resources and Treasure.... The tactics and blood letting were similar to Iwo.... We should have gassed those Bastards, another reason for the Arm Chair WOKE herd to piss and moan about morality.....and atomic bombs...... Bugger the herd that never humps a kit, nor pulls a trigger. All those WizzKids and WiseGuys with their statistics will get you killed, maimed every time as YOU are just a number, a statistic on a ledger.... Robert McNamara killed more working class kids than any Hitler, Mao, Stalin or Hirohito.... He also destroyed Willy's Jeep as former CEO of Ford took the Jeep contract away from Jeep......
who tf is General Kobayashi?
i always thought that hari kari was a waste, as you could have died fighting and inflicted more damage that way.
Iwo Jima's geography, topography and situation was unique. It can't be replicated that often outside of the pacific islands. Like in the Philippines millions of guerilla fighters already held plenty of provinces who then joined the Americans to liberate the rest of the country. Iwo Jima was Japanese soil and part of Tokyo.
Yes, the least they couldve done is conducted night raids with bayonets instead of just suiciding into machine gun fire. But its not like the Japanese were the good guys in this war anyway /shrug
I'll be damned if this channel doesn't deserve the highest honors for virtual content. Absolutely exquisite work!
A good friend of mine father fought at Iwo. He was severely wounded and spent a week or so inside a cave which had been turned into a makeshift field hospital. I remember him telling us the story when I was a kid.
"Good judgement comes from experience. Experience comes from bad judgement." There were a lot of hard lessons learnt from Iwo Jima, all totally avoidable. Unfortunately, such is the price of war.
I am not sure the lessons are totally avoidable. The Japanese being dug in so completely made it very hard to take each position. If they had smart bombs back then they could have targeted each one. But they didn't and cannon fire and even howitzers were limited in accuracy and impact. The Japanese knew they had an advantage with an extensive cave network. But they still lost due to the courage and effort by the Marines and Army forces.
@@earlyriser8998 Oh yeah, I'm sure it was the very first time in WW2, nay, in history, that one was facing an heavily entranched and dug in defender, that was completely unavoidable, good point. *heavy sarcasm implied*
Japanese lost because they were completely overpowered, outgunned, outnumbered, and couldnt get any supply by that point when the US soldiers continued to be sent waves after waves. Sure, heroism and courage were greatly needed for US soldiers, and displayed by them. Specially when their superior officers sent them without proper intel nor proper preparation to their death. No need to come and brag about that courage afterwards, it feels seriously misplaced.
Nah! we should make more war! let more american come in! and then we can destroy them one by one!
As the narrator says other experiences have already had solutions , so why do this ?
It doesn't take a genius to realize you can bypass an island in the middle of nowhere and cut off its supplies.
I think the biggest factor for answering this question is that the US was caught totally off-guard by the uniquely prepared, supplied, fortified, and rationally-led defense Iwo Jima had. It's kind of hard to blame them, too, because what Japan had done with Iwo Jima was something very much at odds with what it did in all of its operations everywhere else. While Hellishly-difficult networks of hidden defensive positions were used by Japan elsewhere, Iwo Jima took the concept several orders of magnitude higher.
It must also be said that Iwo Jima was incredibly unique for how the commander of the defenders repeatedly, explicitly, and personally ordered his subordinates to not conduct banzai charges without his explicit consent. Seeing as these charges were a major Japanese tendency that made clearing out defensive positions on islands far easier, their almost total absence (only two of them occurred, and one of them was actually authorized and led by the commander in a way that subverted how such charges were normally done and, with some luck, inflicted more casualties than normal) just made matters worse.
I'm sure that things would have been very different if the US had taken the operation a lot more seriously and done as much preparation as possible (like with Operation Overlord). However, the pace of the war in the Pacific was such that taking such meticulous and cautious approaches to island campaigns every time would have been impractical in the Pacific.
Realistically, the invasion of Okinawa showed that the US was very much capable and willing to engage in careful preparation and expecting to be fighting a brutal slog against a fierce defense. I imagine that the US simply did not expect that kind of defense to appear as early as Iwo Jima.
I wouldn't call them "well supplied" Supply is a relative term I think, relative to time and the expature of those supplies and compared to the attackers, they had no supplies. The Japanese commander said that the conditions there were far worse than anything he had ever experienced or even imagined. They had to resort to using salt water for cooking, which they didn't to much of because they didn't have anything to cook. They searched for edible weeds and were drinking rain water almost exclusively, at about 1 bottle per man per day. I think it would have been advantageous to at least blockade the island for a period of time before attacking. Let them weaken for a month or so, then bomb them constantly for 3 or 4 days so they can't sleep and then land. Completely bypassing the island is at least interesting.
Iwo being part of the Tokyo Prefecture, someone in the upper echelons must have known it would be difficult. When the fucking brass makes up their mind, they won't be dissuaded by something as trivial as REALITY.
I've never been a decision maker, but have been trusted to inform the decisions of commanders I've been honored to serve. Iwo Jima is a very good example of why you MUST come up with good intel. Lives are absolutely dependent on it.
I don't envy those commanders carrying a burden like that, knowing every decision they make is almost certainly going to cost some of their men their lives, trying to figure out how to make it work with as few losses as possible. A lot of the good officers must have carried that burden of guilt at the losses, even though they knew it wasn't really their fault, but they were their men, so of course they felt responsible for them. No, I don't envy anyone having to make decisions like that.
How would you have gotten good intel on Iwo Jima?
Really? Lives depend on good intel?
This was quite literally one of my questions when watching your other video about the actual invasion itself. Great video
Short Answer: Yes. The Invasion of Iwo Jima eliminated a Japanese air base from which fighters were attacking the B-29s, outbound and on the return journey. It also eliminated a Japanese Radar installation which was providing early warning of incoming B-29 attacks. Iwo Jima provided a safe base for P-51 Mustang fighters to escort the B-29s on their missions to attack Japan. The island also provided damaged B-29s with an emergency landing strip to set down on half way from Japan and their home bases on Guam and Tinian. This alone saved countless crews from the risks of ditching and provided the opportunity to patch up and repair the damaged bombers that would not have made it back home to base.
Mark from Melbourne Australia
It also would have been vital in an invasion of the Japanese home islands. Many forget that the atomic bombs were not guaranteed to force Japan to surrender, and it took Hirohito personally overruling his generals to bring Japan to begin peace talks. Iwo Jima would likely have been used as a launch point for Operation Coronet, or the invasion of Honshu Island.
While the number of aircrew saved was less than the number of Marine casualties, the aircraft and aircrew saved were absolutely more than worth 7,000 KIA.
Have you actually watched the video? All that was mentioned by the author, as well as plausible rebuttals to each of those arguments. I still think the invasion was justified given the intel they had at the time, but it's easy to see why people think it might not have been, and it's not just people judging with the benefit of hindsight either.
@Tomáš Suchý this tbh
But I don't think the land invasion was done right. It would've been better to start with the Vine doctrine and cut the island off and let them starve for a month, amid heavy bombardment from ships and aircraft. Only then make a go for a land invasion.
It was much easier to bypass a very remote island and defeat the ships needed to supply the air base and soldiers. The ships were going to be engaged regardless. The planes were too remote to reach a U.S. fleet that bypassed them and forced the inferior Japanese navy to defend a perceived approach toward Japan itself.
The land battle was pointless. The Japanese soldiers were useless against the U.S. Navy at sea, which the threat to Japan's survival.
Iwo was still used as a base for P-51s and other long range escorts for B17s, B24s and B29s heading to the Japanese mainland, as well as an emergency landing point for stricken bombers returning from Japan.
it certainly had its use for the remainder of the war
Okinawa could have been used for that a couple of months later
Not to mention that there just are not other suitable islands nearby to stage such operations from. The only other islands with airfields in similarly advantageous positions were on Okinawa and as we all know, that battle was also a hellish slog with an incredible amount of casualties
@@hellssatansfc Yeah but why go through two hellish slogs with incredible amount of casualties, when they could have gone through just one?
Because of the fighter escorts launched from Iwo, we were able to inflict way more casualties on Japan than they inflicted on us during the battle. In fact, bombers were able to remove their guns in order to carry more bombs. Hell, any single fire bombing raid more than made up for our losses on Iwo.
Nope, wrong. Your claim is not supported by the statistics and historical research by the USAF and other historians.
I am so enthralled by the videos on both channels, very high quality, I honestly can't wait for the next one to come out. Thank you so much for all the effort and time you put into these videos. It truly shows
"It seemed like a good idea at the time." It is difficult to look back and second guess when more is known now than what was know at the time.
Nah! we should make more war! let more american come in! and then we can destroy them one by one!
Thing is... It *didn't* seem like a good idea at the time. Command was pretty evenly split for and against even when the decision was being pondered. It wasn't considered "good" or "bad" by them either. Just what they went with.
Admiral King thought it was a bad idea. And whatever one might think of his ah... personality, nobody ever said that he was not one of the smartest guys in the room.
I think that such questions are always worthwhile. The fog of war is nearly universal. Commanders will make decisions that look wrong in retrospect because of what they don't know. Later analysis is how we get better decisions in the future. I've loved this series.
I wish I could remember what book I read this in, but I remember distinctly that the battle of Iwo Jima was, in part, a leading factor in the decision to use atomic weapons on Japan. From intelligence gathered during preparations for the invasion of mainland Japan, it was realized that the cost in human life would be simply unacceptable. Japan had planned to hold the entirety of the mainland with the same bitterness and attrition; down to the very last man, woman, and child; that they had with Iwo Jima. There was also a serious doubt that an invasion and subsequent occupation of Japan was even logistically possible. We were also in a mad rush to beat the Soviets, who were already knocking on Japans door from the northwest. Had we not used atomic weapons to bring Japan to the "negotiation" table (read:unconditional surrender to the USA), there is a good chance that to this day Japan would be a Com-block Soviet satellite state.
Fun Fact, every single purple heart given since WWII was minted in 1945, in preparation for Operation Downfall. Some US military planners had projected 60,000 casualties per month, with the invasion taking at very least two years to achieve its objectives. We still have a stockpile of millions of them.
I read somewhere that it was felt to be a decently close analog of the Home Islands given the terrain. Not that other invasions had been picnics, but the prepared mountain and hill defenses were thought to be exemplars for what a homeland invasion might be like.
Imagine what the casualties would have been like given the numbers the Allies would have faced. Suddenly the use of atomics doesn't seem outrageous or like overkill.
Iwo Jima and Okinawa ...
@@alanstevens1296 Yeah, Okinawa was the one that I have heard had more impact on the decision. Iwo Jima was almost entirely military, but on Okinawa the US saw the fanaticism of the civilians as well.
Well put. I always bring up that Purple Heart factoid when discussing the atomic bombings
I think if you weigh the island of Peleliu and the need to invade it against Iwo Jima, Iwo Jima has more significance than not.
Comparing two high causality battles to suggest one is more important ignores that both could have been avoided with no difference to the overall strategic outcome. Maybe finger cancer is better than colon cancer, but regardless no cancer is still best.
They were both equally unnecessary.
Hindsight is 20/20. No US general or admiral will be caught dead bypassing Japanese held islands as long as those islands have airfields and air assets than can threaten the Allied fleet. Everyone's expendable.
Truk is an exception since it's too far from Japan to be resupplied and was totally cutoff once Allied bombings destroyed much of the port facilities and airfield.
hmmmmmmmmm try tarawa
Japan was prepared to bring 600 kamakazi to peleiu. Those planes would have killed 1000s of our sailors and soldiers in the Philippines. Estimates say 10,000+
Very good summary and analysis. You outlined the relationship between Iwo Jima, Okinawa, and operation Downfall brilliantly. Thank You
Nah! we should make more war! let more american come in! and then we can destroy them one by one!
This is the very reason why I would love to see you do a series on the Battle of Peleliu in Palau. Your through examinations and two channels would do such an excellent job covering this often forgotten bloody battle of WWII. Having lived in Palau in the early nineties, it was surreal it is to think on history while standing on a battlefield. Especially when you find a spent 50 caliber shell that has been rusting on a corral reef for 50 years (remember, this was 1991).
Regardless wether you do one or not, I’ve enjoyed both channels and look forward to each upload.
Cheers
Peleliu seem to be backstage to Iwo Jima and some other island battles. It too was hell to pay for island. Could its have been an island to blockaid??? The Japanese navy wasn't as big of treat at that time.
@@robloe7 In my humble, untrained-laymen historian opinion, it should have been avoided all together. However, I think Douglas MacAthur’s ego wanted it so he would be closer to taking back the Philippines. Which, Palau is only 500 miles from Mindanao, so I think that’s why it was selected. But in the end, it wasn’t all that important. With Guam and Saipan taken, and the relative ease of taking Ulithi which is close by, Palau was more or less useless. There were so many islands the US skipped on its island hopping and Peleliu should have been one because of the huge cost of life. As a child, I use to play on the Japanese tanks and ramparts on Pohnpei, which could have been another good island for an airbase, but it was skipped for good reasons and instead they took Chuuk for its large harbor. So I agree with you, a blockade was all that may have been needed at that point…if even that. The Japanese navy and army were on their back heels at that point and they would have just starved in obscurity like those in Pohnpei.
The level of heroic bravery shown during this battle is amazing. It's easy to forget that this was a completely different time and intelligence was "best guess" rather than confirmations. Our country owes so much to these Marines and sailors and soldiers. Ultimately, the battle revealed our enemy would never surrender and assured the use of the atomic bomb ending the war and saving millions of lives making it one of most important and necessary actions of the entire war. Great work on all of your videos!
Japanese bitter-ender tactics led directly to Hiroshima. And for a nation whose government had explicitly embraced total war and rejected treaty obligations to restrict the methods of warfare, that is where it ultimately led. Their chickens came home to roost. What is truly disturbing is to realize that the Japanese leadership actually considered their entire civilian population expendable.
Exactly. People question the perceived brutality of the Americans in the war, but it wasn't. Everything we did was learned as a way to deal with the awful atrocities of the Japanese. From pretending to be dead to catch medics and other soldiers off guard, to shooting medics, to giving school kids grenades and telling them to charge the enemy.
and the US had no qualms about turning an entire civilian population expendable
Once again, an amazing and thought provoking presentation! I've never even considered asking this question before.
Another thing to think about, is if the Japanese were willing to fight and die for a rock in the Pacific, how far would they have gone for the mainland Japan? Dropping the Atomic Bombs was necessary.
The Japanese were horrible, so many lives lost for a war everyone knew was lost by 1943
indeed and if not for the emperor submitting defeat they the military was going to keep on fighting till the last man.
The real end of this saga. See you all Friday!
Yes, because all those returning bombers some of which were shot up, including wounded crew needed closer air bases to land and later launch from. Also it was unknown then that the war would end with nuclear weapons. Iwo and Okinawa were both the necessary lead up for Olympic and Coronet...
Still wasn’t worth the casualties taken. More lives were lost than were saved. You could argue that pilots and crewmen were worth more than grunts but then we would have to argue about how one human life is worth more than multiple others.
@@puenboy1 Because of Iwo Jima, Okinawa was less of a bloodbath then it could’ve been. Many people died for Iwo Jima so more wouldn’t have to die on Okinawa and mainland Japan.
This is kind of like going to the doctor, you never know what it's going to cost until the bill comes due.
For that reason I usually dislike armchair quarterbacking this sort of a decision.
Yes there are some situations where it's plainly misguided but I don't think that's the case here. There were pluses and minuses and of course intelligence said the island was weekly held.
@@M167A1 exactly. While there is use in reviewing after action reports, it isn't fair to the planners for not considering information they didn't have. We also must consider their viewpoint and their expectations of how the war would develop.
Nope. Fifty percent of aircrews that went down in the water were being rescued by subs. A large number of the aircraft that did land at Iwo weren't critically damaged. Many times it was minor damage, minor equipment failure, a little low on fuel or even training flights, but all were counted as "saving lives" regardless if that was the truth or not. Add all that up, and the math says far more Marines were lost than aircrew that were, or would have been saved.The early warning radar on the island was already destroyed, as were the aircraft on the airfields. Additionally, the Japanese actually had early warning from troops and radar on the islands between Saipan and Tinian that weren't taken, and on Chichi Jima, which also wasn't taken. Plus, Japanese fishing boats provided early warning as well. The Island was hardly used for basing fighters because they weren't needed, the Navy could handle fighter sweeps in daylight, and the B-29's changed to night time bombing. The island was useless for staging, as there were no harbors, ports or anchorages. Just like Peleliu, the planners pretty much knew a lot of this ahead of time and went forward anyhow. They could have easily let Iwo wither on the vine, since its source of fresh water was already strained, and there would have been little or no supplies making it to the island. Totally unnecessary. You would have thought that by this point, US intelligence would have realized that all of these islands were going to be dearly held, and none were going to be easily taken.
Much of the postwar questioning of Iwo Jima's significance fails to take into account the cancellation of Operations Downfall & Coronet, the invasions of mainland Japan. Had these gone ahead, Iwo Jima would have made an important base for fighter cover and air support throughout the campaign.
It was already important without an invasion of the Mainland.
Same with Okinawa
Exactly. Just look at Australia retaking Borneo for the Dutch and the British, the Japanese fought until the end.
There was plenty of questioning of the need to invade before the invasion as well.
Nope, wrong. The USAF studied Iwo's role in fighter cover- the P51 pilots had to fly nine hours round trip, which was excessive. The 7th Fighter command determined that only a handful of sorties were flown from Iwo. Your claim is not borne out by the historical record. A grand total of 39 B-29's landed on Iwo because of damage received during missions.
Comprehensive and fascinating, thank you!
Emergency landings for 'routine refueling' are still emergencies. I can imagine fuel tanks leak after home island defenses do their best. Without unbiased reliable data on every landing it would be very hard to know what the true value was, and since there was controversy from the start that seems unlikely.
You pointed out that the emergency landing angle was only used later to justify taking it, but the unexpected heavy defense was not known during planning either.
I see the lack of the impact by King and others as a lack of Vision of the impact of air power on the war and power of closer air fields, bigger payloads, and safe havens if damaged.
No, that's not what "routine refueling" means. When B-29s refueled on Iwo Jima, they did so as a way to extend their flight range in order to reach targets that would otherwise be too distant had they just continued their run from the Marianas. Not an emergency, in other words. If their fuel tanks were leaking, then that would be anything but "routine".
But for 27,ooo young men ?
@@Rusty_Gold85 you saved a lot more pilots than you lost Marines...
The role of the island in airborne emergencies are difficult to assess without close examination of each flight, its conditions, decision-making process of the PIC, and alternatives, before the landing was called. I would wager that without data recorders and satellite navigation, acquiring accurate information for modern analytical purposes is probably not possible for a large number of cases.
However, failing to acquire accurate intelligence to inform your operation is not a justification to conduct that operation.
This is an amazing summary from different perspectives.
thanks a lot for these iwo jima documentaries to both channels (the internal report and the operation room)
Necessary! Fighter cover for the B 29’s and emergency landing for 29s! Those aircraft were invaluable and if they could be repaired or scavenged for parts!
WTF - this is Tuesday, is it not? You know I set my clock by your Friday videos.
Is this like if your team is in Europe, you get a Premiership game on the weekend and one during the week? I'm liking this new schedule.
Needed to get this one out before Bulge starts on Friday! :)
@@TheIntelReport so we are getting more epic content? Friday? Let's gooooooooo!
@@TheIntelReport Well don't waste time talking to me! Friday awaits!!!
(Thank you and well done)
Usually these come out Friday, so this was a pleasant surprise!
Did the Department of the Navy ever explain their reasoning for taking Iwo Jima over the other large islands in the Bonin chain like Chichijima? Was Iwo Jima the only island suitable for airbase construction, or did Navy planners believe that the other islands would have been even more difficult to take than Iwo?
Nah! we should make more war! let more american come in! and then we can destroy them one by one!
Chichjima was also fairly heavily garrisoned, although I don't know that it had the same level of bunkers and tunnels and caves to protect aganinst bombing and shelling. Since it was thought that Iwo Jima had a lighter garrison that it actually did perhaps they though Iwo would be easier to take.
Well, Iwo already had two completed airstips already built by the Japanese. Repairing existing strips is obviously easier and faster than building from scratch. Chichi jima seems a better choice though, with it's natural anchorage.
@@Rocketsong For the navy yes but even to this day that island doesn't have an airstrip. It would have been a better anchorage for the Navy but not totally crucial to any proposed invasion of japan
none of the islands, neither Chichi Jima nor Haha Jima were suitable for airfields, nor did they have suitable anchorages. Iwo wasn't suitable either- no port, no anchorages and no fresh water.
It's very easy to criticize when one has the power of hindsight.
Like nearly everybody posting here. Sheesh!
Thank you for this video, and for answering the question I posed when this series began. A lot of lessons can be learned here, but I think everyone will agree that war is not something that anyone wants willingly.
Really enjoying this longer series. Keep it up.
Terrific video. Good information. (In wars politicians and generals are always coming up with excuses why something bad was actually good. Then there's the old trope, "If we don't continue the war than all those who've died will have died in vain." To which John Kerry, decorated Vietnam Vet and part of Winter Soldier testified to Congress: "How do you ask a man to be the last to die in Vietnam?") Another cynical but real factor, air crews flying very expensive aircraft having more training than Marines who are essentially a man with a rifle, have a higher military 'value'. Two other points are, you often can't know in advance if a military goal is going to be as valuable as you thought, but also it's almost always better that your enemy bleeds to death then you have to fight him. So standing off Iwo Jima and just bombarding it is more cost effective. (We learn about the 'great' battles and victories of the American Revolution, but the incessant guerilla war in South Carolina was probably at least as effective with fewer patriot casualties.)
And what about the Invasion of the Philippines? Was this primarily to satisfy MacArthur's ego? Seems to me it would've been best to by pass the Japanese military there for two reasons. First, Allied lives and ordinance wouldn't have to be expended, but second, by leaving the Japanese on the islands Japan would have to continually try to resupply them, then evacuate them, providing a lot of targets for U.S. Navy submarines and attack aircraft.
(My high school teacher Wm McQueston was in Naval Intelligence during the war, stationed in China. They monitored Japanese naval comms. The Japanese had suffered so many sinkings that commanders were too embarrassed to report them all to their leaders, so the leaders kept ordering convoys to be assembled and less than 10% of the ships would show up.)
All the Purple Heart medals the U.S. military has awarded since 1945 were originally made for the invasion of Japan. We've never run out. But I think two things would happen during an invasion of Japan, first Allied forces would figure out how to fight while taking fewer casualties and second Japan would've suffered a devastating famine during the winder of 1945-6 (One Japanese historian credits the casualties caused by the two atomic bombs with not only ending the war but saving millions of Japanese from death by starvation that winter.) These are arguments for and against how the war was fought. The bigger question is why did there have to be a war with Japan at all? Clearly the decision to invade China and then attack the U.S. were idiotic. The Japanese never ever had the resources or manpower to control the areas of China they occupied, and attacking the industrialized U.S?
In short, it's actually pretty complicated. The Japanese attacked Pearl Harbor to keep the US out of the Pacific while it could secure resources it needed. China was a bit of a mistake, done for resources as well, plus they had a bit of a superiority complex and an axe to grind against China related to Korea. Anyway, Japan hoped that it would be in a good enough position that they could agree to peace in a few years and keep the resources that the Japanese Empire needed. The US had ceased trade with Japan and refused to sell oil, rubber, and metal (and pressuring others to do the same), which Japan saw as a more passive hostile act against it. There are several books on the topic of why the US was "neutral" but not really and had taken several economically aggressive steps against Japan. At that time, many in power were secretly looking for a just cause to go to war in Europe to present it to a predominantly anti-European war public. America as a whole was more than happy to sit the war out since it was another European problem. Japan's attack was a bit of a surprise, though - no one thought they'd actually go for it. A surprise attack was just the thing to enrage the country. This is also why the Pacific war doesn't get as much of a focus. The war in Europe became about stopping crimes against humanity (that bit only really developed in 1944 and 1945, when the camps were liberated), a noble goal. The pacific was different - wholly ugly and focused on revenge as its primary motivator.
Why did the war not end? It's highly debated but can come down do the unconditional surrender policy of the US and internal politics of the Japanese Empire. On the US side, they instituted an "unconditional surrender" policy, meaning they would not accept any truce or peace treaty with Japan except for a complete and total surrender. That bit is a teeeensy bit of a myth since there were technically some concessions at the end. Culture aside, if your only option is to give yourselves and your people up to the mercy of an enraged opponent, would you do it? Or would your people rather fight to the end? On the Japanese side, they technically never offered peace (probably), though certain parts (the "peace party") put out "peace feelers" and were exploring the possibility of the Soviets acting as a go-between. That said, the military faction was much stronger and wanted to fight to the end. So much so that they attempted a brief coup when Japan was actually going to surrender. I guess the simplest answer is: people are people.
@Tales of Insomnia The Japanese told all their soldiers and civilians that the Americans were animals and would torture them if they lost or were captured. (Even though the Japanese were the ones doing so) Not only that but the fanatic religious belief that the emperor was a god had something to do with it. That's part of why the US demanded unconditional surrender. To make sure it couldn't happen again. And honestly? We did a pretty good job helping rebuild after the war.
Many lives were lost taking it, but many were saved after it was taken. Even a veteran of that battle said something among the lines of “After that first crippled bomber landed there, it was all worth it.”
The Peleliu island on the other hand, never really had any military importance as long as other islands. Wake island for example, the US navy more or less used it as proven grounds for the F6F Hellcat, in fact I believe the first or second confirmed kill was a zero that came from there. As the war pushed closer to the main Japanese homeland, Wake was virtually no threat.
This is the video I've been waiting for.
I love these kinds of videos where different perspectives were put into account, all of which are sound arguments based on proven strategies. The island hopping campaign was successful while the bombing of Japanese mainland was also doing well. At the end of the day, the Americans followed through with their decisions and supported each other in accomplishing their objectives. The Japanese high command on the other hand were so stubborn on which way to go and that plagued them all throughout the war.
Iwo Jima and Okinawa were where the Japanese decided to "give the Americans second thoughts about invading the mainland", or words to that effect. It worked, just not how Tojo had hoped.
Great content!
Really good video, good source selection.
Very good and impartial analysis. Great work
I agree that the figure of airmen saved is exaggerated, but according to Robert Dorr in "Mission to Tokyo" the recovery rate for ditched crews was very poor at least in the beginning of the bomber offensive from the Mariannas. After Iwo Jima and Okinawa were taken I imagine the recovery rate was much improved because rescue forces could be stationed closer to the ditching sites. In addition, before Iwo Jima was taken the bombing operations were by necessity unaccompanied by fighters and up to this point daylight raids were the norm. It's easy to criticize the invasion after all was said and done but at the time with all the unknowns and future changes in operational strategy I think it was a valid decision to go ahead with the invasion. If you want to talk about an operation that should not have occurred one need look no further than the Peleliu operation. That was the Pacific campaign's Cold Harbor.
This is all said during hindsight of what happened in Iwo jima. A more suitable question would be. Why did the high casualty rates in the first moments of the Iwo jima fight not trigger "wither on the vine" strategy used in other islands in the Pacific?
Dude has really stepped up his channels. Loving both these with the animations
Often overlooked is the fact that the Japanese had their own medium bombers on Iwo, which they would use to raid U.S. B-29 bases in the Marianas (this from Hornfischer's book on the Marianas). Some of these raids caused significant damage. WWII airfields were notoriously difficult to put out of action for long periods (Battle of Britain). So the alternatives to taking Iwo Jima were enduring raids on the B-29 bases, or devoting considerable resources (and losses) to never-ending strikes on Iwo.
What a mess, Iwo Jima was. The airforce was the only one who gained from this. With the island hopping after Iwo Jima there was bigger air ports available. But taking Iwo Jima taught many lessons taught as you've outlined. An excellent video.
i hate when the words "given out" or "distributed" are used when referring to the # of MoH "awarded" or "earned"
😂 then you wont like how the cib was "issued" in vietnam.
I think the real reasons for invading Iwo Jima were more psychological than strategic. Invading an island which was part of the Japanese home islands had a knock-on effect letting the Empire of Japan know that Okinawa, Honshu and Hokkaido were next.
We needed the Airfield simple as that.
This was a very interesting analysis video.
Great video bro
Capturing the Island gave a forward airbase for the invasion of Japan. If the invasion had gone ahead there would be no debate as to the worth of taking Iwo Jima, Iwo Jima would have been invaluable to stage fighters out of which could have ranged the length and breadth of most of Japan.
What advantage would Iwo Jima have offer as an air base over Okinawa during an invasion of the home islands?
@@MarvinRB3 both locales provide more ground suitable for runways, as well if one locale has bad weather the other is still open for business.
@@gawdsuniverse3282 I don't know, I think you're overestimating the influence Iwo Jima would have in that case. Okinawa had like 10 airfields, one more seems unnecessary in terms of capacity. As for weather, flight operations would be crippled if you can't fly out of Okinawa regardless of whether you have Iwo Jima.
@@MarvinRB3 If Okinawa couldn't operate airfields because of bad weather that makes Iwo Jima invaluable to fly missions from aiding any troops on the ground in Japan.
This sort of thing is like going to the emergency room, you never know what it's going to cost until the bill comes due.
You place your bets and you take your chances.
For this reason I dislike second-guessing.
Thank you gracious ops room 🙏 patiently we wait
I love your work, amazing quality very instructive!
It's unfair to evaluate the taking of Iwo Jima with the benefit of hindsight. No one knew beforehand that the operation would be such a bloodbath. Knowing what we know now, then yes, it probably would have made more sense to bypass and cut off Iwo Jima, while focusing on taking Okinawa.
No. There was still good reason for taking it. Bypassing would have condemned 2000+ b-29 crews to ditching not to mention taking away the fighter base for escorts.
@@TheEvilmooseofdoom No, those flight routes were picked by Arnold because Iwo was there. There is no reason to fly that direction once you have liberated Luzon.
They did know in some places. Like rabaul?😂
Macarthur had a policy of bypass rather than attack head on strong points of less strategic importance. By bypassing he could "wither on the vine" those strong points.
I think Iwa Jima was an intelligence failure. Failing to consider the geographical/geology features of the island. Having dug in. A strategic bombing campaign on Iwa Jima's airfield too would of eliminated Japanese air forces.
I think the US Marines were put into the hornets nest. Probably not the best plan. The US Marines and supporting Navy and airforce were magnificent under the circumstances. The US Marines displayed a disproportionate will to win.
Ultimately the US won. Its forces won the day. Plus as this channel comments. Lessons appear to have been learnt in subsequent campaigns.
I was in awe of the US Marines having seen some of what was reported on this and the sister channel.
The Navy planners also thought that three days of heavy bombing was enough when I believe the Marines asked for at least double that. Coupled with the lack of specialization to break bunkers, that's what really made Iwo Jima so hellish to take.
The ironic thing is that MacArthur insisted on the invasion of Peleliu which turned out to have less strategic value.
It was a no brainer if you were in a damaged B-29, trying to make it home.
MacArthur was not the originator of the bypass theory. That was Nimitz. Macarthur was focussed on the Phillipines, to restore his reputation, not get to Japan to defeat the enemy. The fight in New Guinea is a great example of Macarthur hopping along the coast, chasing the Japs, long after they had been a force to worry about. But he gets a jumping off point to the Phillipines.
And Macarthur attacks New Britain, home of Rabaul, in late 1943 and fights a nuisance action to the end of the war. They never bypass Rabaul, the neutralize it instead.
@@stopspammandm MacArthur didn't actually insist on taking Peleliu. MacArthur had no direct control over operations in the Palau Islands. It was actually Nimitz who decided to go ahead with the operation despite recommendations from Halsey that it would be more practical to send the 1st Marine Division to Leyte.
After reading some of the comments - It amazes me how so much more "Brilliant" YT posters are than the commanders at the time.
Funny, that. Innit?
An interesting and well written presententation. Plenty of food for thought in areas I had not condidered before.
There are always battles, that after the fact, the justification can be questioned. Hurtegen Forest in Germany, and the invasion of Peleliu are prime eamples. Nimitz later regretted the later and Eisenhower the former as being unnecessary. Hindsight is 20/20. I have read extensivley about the Pafic war and personally believe that Iwo was worth the cost, but everyone has an opinion.
There's thousands of Americans alive today because their fathers had that Island to sit down on
This is awesome,, by the way pls consider make some Korean war history...
I just read the title. The purpose of Iwo was functional. The projection was an invasion of the home islands and there were only 2 locations to land on Japan. Taking Iwo was a must for aircraft until the invasion and as the closest base for operational use during the invasion. Actually, the first aircraft to use the runway for an emergency occurred before the island was fully secured.
Today this is amazing, I am sure, but I knew this stuff in the late 60's in 4th grade.
It is amazing to me how much the old tech and history is so shocking to American kids today. Next you will make a video about the purposes and uses of light switches back before remote switches.
2250 damaged bombers landing there with 8-10 guys per bomber is a powerful argument. That’s from a U.S. Marine who hates the loss of life of the Marines and Sailors spent taking the island. Also given the incorrect information believed by planners the DECISION to take it makes great sense. In hindsight, much less so.
OK editing my response after rewatching based upon my Dads comments. If the safety of damaged bombers wasn’t considered in the pre-invasion discussion taking the Island makes less sense. Only if you were sure it was a cakewalk would the rationales put forth make sense. But if you thought it was a cakewalk why bring the massive forces involved?
Hindsight is 20/20. We'd all be better than Napoleon if we knew the results before they happened.
Time was a big factor. If given proper time to bombard or fully starve out the defenders a full invasion might not be needed. Then again the amount of naval/air power required to keep resupplies from happening are substantial.
Well balanced, well researched. Great video.
Great video! I had read somewhere that a significant factor in the decision to take Iwo Jima was a result of the competition between the Army and Navy in the PTO. Maybe you could cover General Pershing's final offensive in WW1, days before the Armistice.
Great segment, really first class!
Hindsight! I'm sure they thought it would be a short battle. small island like that. But I agree there was one or two more questionable islands.
Arguments from both sides have valid points. It's sad and unfortunate that we lost so many young men against a relentless enemy.
Having videos like this help me learn so much. Can you guys make a video on the invasion of Okinawa
Even with our exemplary Codebreakers, getting an accurate picture of the realities with Japanese preparations and force status on Iwo turned out to be wholly inaccurate. Having walked those Black Sand Beaches of Iwo in 2018, it is easy to imagine the horrors experienced by both sides in February and March of 1945. I like the way that both sides have been portrayed here: Tenacious, brave and proud. And likely scared spit-less at times within the scope and scale of this battle. May all of these heroes rest in peace.
The Japanese had 3 airfields and they could easily intercept and shoot down our bombers from Guam, Saipan and Tinian
with the ability to get fuel there lol.
Nonsense. A blockade + bombardment would have erased any military activity on the island. The question was not about them. It was about US urgent need or not for their operation.
@@humpteedumptee8629 The Japanese had fuel to the very last day of the war, as proved by the refueling of the I-400 class submarines. At Korea.
@@davidb2206 he meant getting fuel to iwo jima. The Americans could easily blockade the island, detroying their ability to operate aircraft from there.
@@MarvinRB3 You assume too much. The Japanese got fuel into Guadalcanal with the U.S. Navy all around. Same with place after place, later. Philippines. They got the I-400 submarines refueled in Korea even though the U.S. was patrolling the Sea of Japan in the very last weeks of the war. It was prudent to Iwo and it worked to our advantage in the war effort (and timing). No further argument about it.
My dad was in the Navy in the Pacific and he used to say there was no need for Tarawa and some other islands, saying we should have just starved them out.
Great summary!!
The invasion of Iwo Jima was necessary because of the willingness of the Japanese to defend it. japan considered Iwo Jima part of Japan. Conquering Iwo Jima was the US first attempt at defeating Japan home territory. It may have not been necessary from a strategic point of view but it was necessary from a psychological one. Before it was conquered, diehards in Japan might still think Japan was unconquerable but afterwards, everyone knew Japan would lose the war.
So 10' of thousands of losses are justified for a photo op?
That just adds to the valid, prudent, sound tactical and logistical reasons for the operation. It may have been down the list as an added advantage.
@@davidb2206 Those reason may have made sense when planning the operation, when low casulties were expected.
But in hindsight, knowing the enormous cost Iwo Jima actually entailed and how little it ended up helping the war effort, it seems clear Iwo Jima was a huge mistake.
@@neshirst-ashuach1881 But would Japan surrender after the atomic bombs if they still thought they were invincible? The Japanese never surrender. But if they could be defeated, maybe...
Sometimes you have to kick the enemy in the balls just to prove you can.
@@neshirst-ashuach1881 Wrong. Hindsight doesn't work and is not a valid argument. Nobody knew what the casualties would be. The Navy even reduced the prep naval bombardment that Gen. Smith wanted.
Had the US waited a few months, Iwo would have been an excellent test for the atomic bombs. Could even gone ashore after awhile and seen if any survived the blast and how the bomb affected them.
I was thinking the same thing. It would have shown the US’s capabilities to Japan (and the world) and have very few civilian casualties. However Fat Man and Little boy were very hard to make and very expensive, plus who would believe one bomb did so much damage. Hitting Mainland Japan show the Japanese that their were not winning this war.
Hindsight again, because ON THAT DATE, even General Groves did not know that the first a-bomb would be ready.
Wasting one of the two bombs on Iwo Jima would have done nothing but harden the Japanese resolve to not surrender. Because they would not have believed the evidence that Americans sent them, in the aftermath. They would have simply dared us to drop more bombs (and we only had one more to drop). No. As disgusting as it is to say out loud, Hiroshima was absolutely NECESSARY. Because the Japanese could not ignore an A-bomb dropped on their own home soil!
People who say the US nuclear bombings were totally unjustified really need to consider the statistics. 800,000 to 1,500,000 US soldiers lost, and another 5 - 10 million Japanese civilians. Japan is bigger than Italy, it had a bigger population than Italy, it had similar terrain, it had a population willing to fight unlike Italy, and it had been stockpiling weapons to defend the home islands for this exact purpose. Italy surrendered halfway through and still was a bloody fight. Not to mention the 20,000 Chinese people dying every single day the war carried on. I get it, targeting civilians is fucked up but there is no such thing as a clean war. Civilians will always die. WW2 was an example of a "Total War" (yes the game series gets the term from this) which is a war waged on the very infrastructure and industry of a country as well as its military. So when the US dropped leaflets warning the civilian population of japan not to be in certain cities filled with military industry because they were going to be destroyed the US had gone above and beyond what was required of them.
Keep making these. Just trying to help your algorithm
I don't think a place like Iwo Jima can be bypassed. I think 20,000 airmen we're saved using Iwo Jima for emergency landings. Rabaul was bypassed and I count it a good example because it wasn't that useful if overtaken.
Also, why didn't the US went for Formosa, today's Taiwan? With that island conquered, US would have had direct access to mainland China and cutting off Japan from their forces there would have spelled catastrophy for their war economies and morale. Is it because America's command viewed the task too difficult even for their experienced and battle-hardened marines to overcome? With the Philippines reclaimed, next plausible operations for the Americans- just looking at the maps- was Formosa, instead they choose these small islands like Iwo Jima and Okinawa. Why?
Because we didn't have to. The target was Japan, not pushing Japan out of China. They were playing to win the war quickly, and striking the Japanese mainland would do that a lot better than a liberation of China.
@@sid2112 What this man said. Additionally Formosa is known as the “Fortress island” for a reason, it’s terrain is particularly suited for defense. Limited number of landable beaches, a massive difficult to traverse mountain range, the usual. So it would be a target that would be really costly to take (similar on order of magnitude to Okinawa or Iwo), but basically not advance the U.S war goals in any meaningful way.
Taiwan is an absolute nightmare to take. It would have been Iwo Jima x100. Just wasn't worth it.
@@sid2112 Yeah, but from a strategic view point including that of the post-war, liberation of China has its own prizes. Japan switched their supply chains coming in from the Dutch East Indies to the land routes passing through China's interior, Korean peninsula and finally to their heartland after American's comeback at the Philippines. Retaking China by in large would completely cut off Japan from the rest of their empire, severly damaging their war efforts. Also, in terms of post-war politics, which had already been in play after the allies' victory was fait accompli, landing in China and linking up with the Chinese nationalists would have had the effects of deterring the communists, who had already garnered significant footholds in the northern China. Reinforced by the Americans, nationalists could have performed way better than they had in the civil war that ensued, and the world today could have looked very different if different decisions were made in that time.
@@paulhan1615 They were already choked off of the Dutch East Indies, and the idea was to end the war, not prolong it.
The Chinese Nationalists were not a unified or effective fighting force at the time, or any time thereafter, really.
Landing in China would not have eliminated the necessity of landing in Japan as well, so why bother?
Our mistake was not during the war but after when we failed to support the Chinese Nationalists.
This channel is a god sent
Another discussion I haven't really seen is whether on Okinawa the Allies could have halted after the first week, by which time they'd secured a majority of the island and most of the major airfields with a minimum of casualties, leaving the main concentration of Japanese forces who were holed up in well-prepared fortifications in the southern part of the island. Clearing that section would take over two months of extremely heavy fighting, for no clear strategic advantage, while the fleet remained under kamikaze attack for most of that period as well. This hypothetical assumes the Allies could have figured out in real time that the southern part was going to be extremely difficult to take, when the reality was that they didn't know where their opponents had disappeared to, until they started to encounter heavy resistance once they advanced up to the first main defense line in the south of Okinawa.
You can't take part of an island and leave thousands of troops to just sit there and let you keep it.
@@kristopherloviska9042 Leaving garrisons isolated to starve out happened numerous times during the island-hopping campaign; Rabaul was only the most infamous example. If you have all the strategically important parts of an island, which in both Okinawa and Iwo Jima were the airfields, what's the point of hammering against heavily fortified positions for land that isn't all that valuable? I can see infiltration as being an ongoing hazard, but that brings the Japanese out into the open where they were much more vulnerable; the losses would likely have been far less than the bloodbath that was the second half of the fight for Okinawa.
Iwo Jima was a vital strategic position. It was never envisioned as a fleet base or jumping off point for future landings. It's sole purpose was to utilize the 3 airfields to permit aircraft with mechanical issues or damage during bombing runs on Okinawa or the Japanese Mainland, to land there, as flying to fields on Guam or Saipan were too far. In fact, while the fighting on Iwo was going on and the first airfield secured, planes were landing on the island.
While capturing Iwo certainly had its benefits, I can't see it being justified at the time nor in retrospect - 6000 dead, 19,000 injured? What a price.
Tell that to the aircrews who would be dead if not for that island. Nearly 2500 emergency landings by B-29's.
@@TheEvilmooseofdoom I'm going to sound like a dick, but watch the video, that topic is covered and "debunked". The vast majority of those "emergency" landings were for routine things like refueling.
Iwo Jima was also needed as an emergency landing strip to save B-29s and crews that either could not complete their missions to Japan or complete the return trip to their home bases after bombing Japan. The fact this justification was not on offer soon after the event in WW2 should not be that surprising...
B-29 loss rates did not justify 7,000 dead and 20,000 wounded Marines, Sailors, and Soldiers.
It's much easier to evaluate the merits of a military campaign after the fact. Looking at it from the perspective of its planners, it was one more step leading to the ultimate goal. And, at the time, Iwo Jima was another stepping stone toward the invasion of Japan. It just so happened that future events made that unnecessary. Could the operation have been better planned, resulting in fewer casualties? With the advantage of hindsight, of course. One could make that observation about even the most successful military operation.
Absolutely necessary. Once you learn of the campaign strategy you know we couldn’t simply leave this island. It was never considered inconsequential. It was an airbase larger than wake or midway which we all know how important they where.
It had ZERO to do with naval power. It had everything to do with the increase in American air support in the OA. This OA reached mainland China and Japan.
In fact if we hadn’t taken Iwo the inola would have flown over, or around iwo. An impossible task if the Iwo airfield was intact.
Even insinuating iwo was not of VAST strategic importance shows lack of knowledge.
Monday morning quarterbacks always win the game.
I haven't watched, probably never will, but one answer to why not just blockade it is that it was needed by the air corps.
My father was in the USMC, on Guam. He would have been part of the invasion of Japan, in which case I would not exist. He told me that after Iwo Jima, the flyers were so grateful for being able to land at Iwo Jima when otherwise they would not be making it back, that they would do anything for the Marines. (My father got a joy ride in a bomber.) So that is one thing to consider.
Babe wake up! The Intel Report just posted a new Iwo Jima video!
This has been a great series. I'd love to see a follow-up on Okinawa!
I have often wondered why the Allies didn't just starve the Japanese out rather than sacrifice so many lives to take the island.
Iwo Jima and Okinawa both had to be invaded. Iwo Jima is about 750 miles from Tokyo. Okinawa is about 950 miles from Tokyo. Long range fighters like P-47N's and P-51 Mustangs needed bases within flying range. B-17's, B-24's and B-29's bombers all needed closer bases to attack the Japanese Home Islands. The only way to end the war in the Pacific without an invasion of the Japanese Home Islands were to capture bases close enough for bombers to reach targets in Japan. Also Iwo Jima became a sanctuary for shot up or mechanically stricken bombers to land safely without ditching in the ocean. Iwo Jima saved just as many or more aircrew's lives than it cost to take the island. So the short answer is Iwo Jima and Okinawa both had to be taken by ground invasion to move the bomber line forward. Guam and Tinian are too far distant for even modified B-17's and B-24's to bomb the Japanese Home Islands. Also B-29's had notorious engine fire problems. Iwo Jima saved lots of aircrew and B-29 bombers that would have been lost at sea.
Great video Thank you
When you consider our invasion plans included 495 ships, 17 Carriers, over 1,100 planes, and upwards of 100,000 total men, it's hard to believer they anticipated "light assistance".