Strategic Capabilities of IJN

[Caiaphas]

Forgive me if this has been covered by some other keystone work of military history, but I've been reading Shattered Sword recently and I just had to ask: why in blazes did the IJN, and in particular Admiral Yamamoto, tend to leave so little room in his planning for strategic redundancy? Why is it that he tried to carry out three simultaneous operations across a span of ocean so broad as to require several days at flank speed for any of his other forces to come in support of the Midway fleet? Why did he, doctrinally, have such shoddy reconnisance?

It just seems baffling to me that someone like Yamamoto, who knew exactly how much more materiél the American Navy could bring to the game, would not try to concentrate his own forces as tightly as possible, and I can't think of a decent reason for it aside from a temporary attack of insanity.

[Tribble]

The biggest factor was that the IJN had no idea that the USA had broken their codes. By attacking multiple points at once the goal was to keep the US off balance, and keep bulk of their forces and primary objectives concealed. Unfortunately for them the US knew Midway was the primary target and was able to concentrate their forces. They also assumed that the Yorktown wouldn't be available due to the damage it received during the Battle of the Coral Sea, and with the US only having two carriers the forces at Midway would be more than enough should they show up.

In addition, Yamamato knew that he couldn't concentrate his forces too much. He wanted to draw the remaining US carriers out and sink them, and if he put all of his ships into a single big fleet the US fleet would just decline battle as at that point the Japanese fleet greatly outnumbered the American fleet. He kept his main group of battleship well behind the carrier task force in order to keep them concealed, and believed that while the Americans were busy fighting over Midway they would eventually enter the fray and sweep the Americans aside. He did not anticipate the Americans to react as quickly as they did, nor with as much force as they did. And to be fair, were it not for the breaking of the IJN's naval codes he may very well have been right. In hindsight he obviously dispersed his forces too much, but at the time his plans at least seemed plausible.

EDIT: And yes, the Japanese later acknowledged that their planning was shoddier than it should have been as they had become overconfident due to their multiple victories earlier on. Even Yamamoto wasn't entirely immune.

[Isolder74]

There is more to it as well. Due to training and production limitations, both the ships Shōkaku and Zuikaku were out of the action because both of their airwings were slaughtered at the Battle of Coral Sea(not only in the battle but in the failed night landing where most of the crews drowned). Shōkaku was damaged enough that it still would have been unable to participate in the Midway action but Zuikaku had lost almost all of their pilots making it unable to join as well. The planning was set up with so little strategic depth because they just didn't have the ships to pull off their elaborate goals with. The Midway plan just accentuates this more then any other simply by virtue of the sheer size of the plan itself. They had built into the plan reusing units from Coral Sea in the Midway Operation simply because they lacked the ships to make multiple operations. Their plans did work around units being unavailable but tended to do so without considering the implication of those units not being present assuming the training of the men will cover any deficiencies.

Admittedly, they did have some of the best trained aircrews of all of the combatants at the opening of the war they just didn't have any capacity to replace those crews. They also had the best night fighting capability of any of the navies during the war. There is a place called Iron Bottom Sound because of this night fighting training. It was because of those early night battles causing so much damage they they saw potential for success for their battleships doing massive casualties during the Battle of Leyte Gulf.

The IJN never had much strategic depth often because they would have to stockpile fuel before every major engagement just to ensure they can reach the battle and return from it. As the war went on this got worse and worse because the Japanese refused to consider the protection of cargo vessels as important. US subs were sinking oil and material transports at such a rate that even with captured oil field in what is now Indonesia they just didn't have the fuel to even train upcoming battle hence the major losses at the Battle of the Philippine Sea(AKA the Great Marianas Turkey Shoot.)

You can see their narrow focus in the design and layout of their bomber aircraft. Their Dive bomber(Val) can only carry a single 250 KG bomb on the centerline mount or 2 60 kg bombs under the wings with a center fuel tank(In theory they could carry all three bombs at once but it wasn't recommended). Their Torpedo Bomber(Kate) could carry either a single 800 kg torpedo, a single 800 kg bomb, two 250 kg bombs or six 132 kg bombs. None of their aircraft had capabilities to drop their bombs other then single salvos as their combat doctrine favored precision over versatility. The Kate had centerline mounts all slaved together and two wing mounts so in theory could drop bombs on up to three different targets(the wings mounts only able to handle 250 kg bombs or smaller). In contrast, the American Devestator Torpedo Bomber(admittedly already obsolete) could handle one Mark XIII torpedo, one 1,000 lb bomb, two 500 lb bombs or twelve 100 lb bombs. Those loads(other then the torpedo and larger bomb) could be attached and dropped with various mixes of the ordinance based on mission and targets meaning even the worst of the US Bombers could attack more targets and do more damage then any Japanese unit could.

[Sea Skimmer]

Forgive me if this has been covered by some other keystone work of military history, but I've been reading Shattered Sword recently and I just had to ask: why in blazes did the IJN, and in particular Admiral Yamamoto, tend to leave so little room in his planning for strategic redundancy?

Because the entire expansion of the war in the first place was a last ditch gambit to avoid total strategic defeat. Yamamoto knew America absolutely would have the power to counter attack, he wanted to push out the lines as much as possible before that happened. He definitely failed to appreciate the ability to which the US would be able to just bypass most outposts...but the US didn't appreciate this either until after Tarawa, and that's November 1943.

Anyway the entire idea of attacking the colonial powers directly was a last ditch gambit in the first place. You can't really ask for reserves when the entire war was launched using the reserves...

The fundamental problem was 100% of target Japan could attack ever were just US outposts, while the Doolittle Raid showed that almost by default the US could strike directly at Japan, something the Japanese had thought could only really happen after the US had a nearby land base. They had very little assigned to home defense, but it was sufficient to have stopped a conventional US carrier strike.

Why is it that he tried to carry out three simultaneous operations across a span of ocean so broad as to require several days at flank speed for any of his other forces to come in support of the Midway fleet?

This wasn't really more demanding an idea then what had already been carried out in the prior 100 days in terms of operating tempo. The difference was the operations would face effective operational level resistance for the first time. That had to happen at some point, Japan had good reason to be confident it could inflict heavy damage on any plausible enemy force encountered, and the original 100 days, roughly, plan of the Centrifugal operation had allowed for as much as 1/3rd the entire IJN being sunk in the process. Instead they lost I think it was 11 ships total including transports, including only a few destroyers for combatants.

At that point taking on additional risk isn't completely unreasonable. It proved to be a very poor idea to split the IJN carrier force, but the very idea of having 1 large force was less then 2 years old, and precisely one of the reasons why Japan had formally only used dispersed carrier operations was what happened at Midway. If 1 ship gets found, which it surely will be because of its aircraft buzzing around, that means ALL the carriers get found.

Midway and the Aelutions had the same objective, eliminating plausible allied bases to bomb Japan from, as Japan was convinced the Doolittle Raid was only linked to and not launched from US carriers. Inflight refueling was a known thing at the time ect...

The Coral Sea operation was opportunistic, but the operating area was also becoming a major center of allied air power and Japan wanted to attack it to prevent it reaching a critical mass they wouldn't be able to ever handle. Instead that's exactly what happened rapidly after the failure of Operation MO.

Why did he, doctrinally, have such shoddy reconnisance?

He didn't, if you want doctrinal stuff. The operations exceeded doctrine, and where the first that did not benefit from prewar preparations. Doctionally the IJN's primarily air recon force was all its land based flying boats, backed up by large numbers of cruiser launched floatplanes. Carrier aircraft were supposed to be held back as much as possible for the strike role. Since the idea of a unified carrier force was itself new full operating procedures were something in flux. The USN made MAJOR changes to the way it operated in the first six months of WW2 too. But it kinda had this six months as a training and working up period, making only token raids on Japanese holdings, while the IJN was in pure combat mode.

Since Midway was so far east the land based seaplanes had little value, and submarine scouting really wasn't a viable replacement when US carriers could take so many different routes to defend Midway. Meanwhile a large number of cruisers were required to escort the various invasion forces, instead of being on hand

Doctionally the IJN was supposed to defend Japan, not takeover the world. It's not really surprising it failed, and really, if you look at what crazy happened, easily enough the battle could have turned out as 2 Japanese and 2 American carriers sunk, and a landing made on Midway but probably completely destroyed in the process by the ground defenses. The real thing Japan never counted on was that the Islands were seriously defended and all its naval operations could mean squat for it.

[Caiaphas]

In addition, Yamamato knew that he couldn't concentrate his forces too much. He wanted to draw the remaining US carriers out and sink them, and if he put all of his ships into a single big fleet the US fleet would just decline battle as at that point the Japanese fleet greatly outnumbered the American fleet. He kept his main group of battleship well behind the carrier task force in order to keep them concealed, and believed that while the Americans were busy fighting over Midway they would eventually enter the fray and sweep the Americans aside. He did not anticipate the Americans to react as quickly as they did, nor with as much force as they did. And to be fair, were it not for the breaking of the IJN's naval codes he may very well have been right. In hindsight he obviously dispersed his forces too much, but at the time his plans at least seemed plausible.

Okay, yeah, I can see what you mean, but the issue that I have with that line of argumentation (specifically the point that he didn't want to scare them off with too massive a fleet) is that if they threaten a especially strategically US position, then they have no choice but to reply, because to just let them take it unopposed would be to consign themselves to destruction. So the question that arises from that is, did the Japanese equivalent of ONI know whether the US knew they had any land-based bombers that could attack Hawaii from Midway? Because if the answer to that is "the Imperials believe that the US thinks they can bomb Hawaii from Midway", wouldn't that threat force Nimitz (in their thinking) to send out the fleet regardless of how strong their own forces were?

The planning was set up with so little strategic depth because they just didn't have the ships to pull off their elaborate goals with. The Midway plan just accentuates this more then any other simply by virtue of the sheer size of the plan itself. They had built into the plan reusing units from Coral Sea in the Midway Operation simply because they lacked the ships to make multiple operations. Their plans did work around units being unavailable but tended to do so without considering the implication of those units not being present assuming the training of the men will cover any deficiencies.

So it was just a matter of their ambitions not being logistically feasible and their high command being basically too arrogant to believe that they could ever be stopped?

Incidentally, you wouldn't be able to recommend a good book that covers the Battle of the Philippine Sea and the later Philippine campaign?

He didn't, if you want doctrinal stuff. The operations exceeded doctrine, and where the first that did not benefit from prewar preparations. Doctionally the IJN's primarily air recon force was all its land based flying boats, backed up by large numbers of cruiser launched floatplanes. Carrier aircraft were supposed to be held back as much as possible for the strike role.

You know, that sounds weirdly similar to the US "island-hopping" strategy to me, if you view it as a prelude to an attack. Take an island, use it as a staging base for flying boat recon, use float planes from cruisers to scout out the next island as the fleet approaches, invade, rinse and repeat.

Thanks to all three of you for the response; it's been very illuminating.

[Isolder74]

The best place to start looking at the IJN and their performance in WW2 battles is http://www.combinedfleet.com and go through the information there. One of the best books on the Battle of Leyte Gulf that you really need to read is Last Stand of the Tin Can Sailors but there are lots of books covering it. Also look up and watch Battle 360 on the USS Enterprise.

For books on the marinas campaign google search the great marianas turkey shoot and you should get some good places to start. Looking for books by Jonathan Parshall and James D. Hornfischer is also great places to go.

Edit: Also this Midway lecture

[Simon_Jester]

You know, that sounds weirdly similar to the US "island-hopping" strategy to me, if you view it as a prelude to an attack. Take an island, use it as a staging base for flying boat recon, use float planes from cruisers to scout out the next island as the fleet approaches, invade, rinse and repeat.

Hopefully the big guns will correct me on this if I'm wrong, but the key difference is that "island hopping" is explicitly an offensive strategy, while insofar as the Japanese had any coherent notion of how to fight a sea war in 1941, it was a defensive strategy.

All Japanese strategy against the US goes back to the Decisive Battle, the idea that they could expect the entire US Pacific Fleet to come rushing out to defend Manila, then whittle it down with air and submarine and surface torpedo attacks until it had been softened up for the battleships to muscle in and finish it off. This isn't to say that the Japanese didn't know how to stage a raid (obviously) or how to expand into a power vacuum of lightly garrisoned islands by seizing them. But as soon as they started trying to integrate such actions into a larger strategy, they were in unfamiliar territory, having to improvise their solutions to everything.

As noted above, Yamamoto was basically just trying to seize as much territory as possible while land grabs were easy, so that he could start implementing a defensive strategy as far as possible from the Home Islands. Everything after Coral Sea was Japan trying to improvise an answer to the eternal question of a dog who chases a car and has that one, perfect moment of inconceivable, glorious success:

"Okay, and now what do we do when we've caught it?"

By contrasts, the "island hopping" strategy was a coherent, internally consistent whole where all the necessary materiel and types of forces were already available (or could be quickly built) to do the job.

[Sea Skimmer]

Okay, yeah, I can see what you mean, but the issue that I have with that line of argumentation (specifically the point that he didn't want to scare them off with too massive a fleet) is that if they threaten a especially strategically US position, then they have no choice but to reply, because to just let them take it unopposed would be to consign themselves to destruction.

The reason the forces were so broken down at the tactical level is simpler I think then any specific operations plan. The Japanese had long emphasized a night surface battle as the main hope to beat a stronger US fleet, but realized that large formations would be impossible to control. So they just kept the forces broken down all the time, they could join together in daylight if needed easier then they could split up at night.

The problem is this also led to Japanese exercises often being canned in peacetime, elaborate plans unfolding like clockwork for torpedo attacks is one description, and distorting the true effectiveness of subordiating command vs the loss of concentrated firepower that resulted. But at Midway that wasn't going to matter because even if the US battlefleet did come out it was going to be seriously outmatched. Being all slow, and Yamato being real and all.

If you look at all the East Indies invasions, Japanese forces were very dispersed in all those actions too, which is how the Battle of the Java Sea managed to happen as it did. But in all those actions Japan enjoyed overwhelming air superiority from land bases and its carriers only reinforced and expanded that umbrella. The main effort was always land based, and from large numbers of seaplanes flying off tenders with the invasion forces.

Some of the seaplane tenders were in fact carrying equipment for the Midway occupation force during the Midway operation instead of planes. But no site existed where they could setup in support of the operation anyway.

So the question that arises from that is, did the Japanese equivalent of ONI know whether the US knew they had any land-based bombers that could attack Hawaii from Midway?

The Japanese knew what the planes were that attacked them, the B-25 had been intended for major export by the US so it wasn't too secret or anything. Japan seems to have been pretty confused, but air to air refueling was a known thing in 1942. It just wasn't ever practical in the war for large scale operations, the USAAF tried at times with B-24s.

More directly the problem just was the IJN had no further plan, and highly objected to the IJA position, which was that all further expansion should cease. The IJN thought that was suicidal by default, and basically right. The only way to win the war would be an unending stream of banzai super victories!

Because if the answer to that is "the Imperials believe that the US thinks they can bomb Hawaii from Midway", wouldn't that threat force Nimitz (in their thinking) to send out the fleet regardless of how strong their own forces were?

Yup. The Americans would have no choice but to sortie in maximum force to oppose an attack on Midway, because from Midway Japan would gain a major strategic leap forward into a new island chain they could not otherwise threaten from a shore base, and by having recon coverage on Oahu would know the status of the US carrier force. The US had no way except radio intercepts at this stage to track the Japanese force, nor did the US know how many flight decks Japan actually had. We knew nothing of several real carriers, and yet thought several fake ones generated by false Japanese traffic existed of different classes.

You know, that sounds weirdly similar to the US "island-hopping" strategy to me, if you view it as a prelude to an attack. Take an island, use it as a staging base for flying boat recon, use float planes from cruisers to scout out the next island as the fleet approaches, invade, rinse and repeat.

It's basically how the original Japanese expansion worked. But Japan was only putting garrisons of 200-400 men onto most of the sites they took, about 200 people to run an airfield or seaplane anchorage, and 200 men manning anti aircraft guns defending it who could be infantry in a pinch.

SO the whole Japanese force that entered the south-west Pacific area was only about one 3,000 man brigade in strength spread all over, before it was to be reinforced for the Coral Sea Operation.

Japan just didn't realize at all that in the five months since the war began that the US had significantly reinforced all its remaining outposts and Commonwealth possessions throughout the entire mid Pacific. The MIdway ground operation would have been fine had Midway had the 700 men Japan thought, but it was instead thousands. Meanwhile Fiji and Samoa have whole divisions on them, and Palmyra and Johnston Atoll were like Midway, defended by brigade scale forces with a serious amount of duel purpose artillery and 5-7in shore guns.

But Japan had reason to not think t hese islands would be heavily reinforced, to a point, because of EXACTLY what happened to Japan later! The strong garrisons could be bypassed and left to wither; though on some of the allied islands you could actually grow enough food to survive. That was not true of say Truk. Even after Midway Japan did not reinforce its own eastern outposts all that heavily, though they kept building airfields up. It was only after Guadalcanal and Makin that they suddenly decided to divert first five and then another bunch of divisions from China east. Most ended up bypassed, and in hindsight nearly all could have been. In reality Japan was crazy to seriously try to hold anywhere east of Saipan, which was where it wanted to fight in prewar plans too.

[Tribble]

The reason the forces were so broken down at the tactical level is simpler I think then any specific operations plan. The Japanese had long emphasized a night surface battle as the main hope to beat a stronger US fleet, but realized that large formations would be impossible to control. So they just kept the forces broken down all the time, they could join together in daylight if needed easier then they could split up at night.

The problem is this also led to Japanese exercises often being canned in peacetime, elaborate plans unfolding like clockwork for torpedo attacks is one description, and distorting the true effectiveness of subordiating command vs the loss of concentrated firepower that resulted. But at Midway that wasn't going to matter because even if the US battlefleet did come out it was going to be seriously outmatched. Being all slow, and Yamato being real and all.

Right, but IIRC part of the reason why the fleet was split for the Midway Campaign was for the specific purpose of keeping American forces off balance and unable to determine the full size of the fleet sent against Midway. Yamamoto could have just as easily kept his main force with his carrier fleet instead of keeping it hundreds of miles to the rear. He deliberately kept his main force back to keep them concealed as long as possible. Had he known the Americans had ID'd Midway as the primary target (or that the Americans had 3 carriers available instead of 2) I highly doubt he would have done so.

That's not to say that his plan was overcomplicated - obviously it was. However, IMO Yamamoto was well aware that "Giant Big Fleet Smash Midway!" wouldn't work if his goal was to lure the Americans into a battle. He needed to make it something that the Americans felt important enough to fully commit to, but not so obviously overwhelming in Japan's favour that the USA would simply decline battle.

The Japanese knew what the planes were that attacked them, the B-25 had been intended for major export by the US so it wasn't too secret or anything. Japan seems to have been pretty confused, but air to air refueling was a known thing in 1942. It just wasn't ever practical in the war for large scale operations, the USAAF tried at times with B-24s.

More directly the problem just was the IJN had no further plan, and highly objected to the IJA position, which was that all further expansion should cease. The IJN thought that was suicidal by default, and basically right. The only way to win the war would be an unending stream of banzai super victories!

IIRC the IJN (well Yamamoto anyways) were well aware that they had no real hope of outright winning and their goal was to win enough victories to bring the Americans to the negotiating table. At no point did they seriously consider going after Hawaii or the mainland, and even Midway was stretching it logistically wise.

Yup. The Americans would have no choice but to sortie in maximum force to oppose an attack on Midway, because from Midway Japan would gain a major strategic leap forward into a new island chain they could not otherwise threaten from a shore base, and by having recon coverage on Oahu would know the status of the US carrier force. The US had no way except radio intercepts at this stage to track the Japanese force, nor did the US know how many flight decks Japan actually had. We knew nothing of several real carriers, and yet thought several fake ones generated by false Japanese traffic existed of different classes.

Midway was an important base, but IIRC it wasn't critical enough for the USA to sacrifice 3 of its remaining carriers if they knew the odds of successfully repelling an invasion were overwhelmingly against them (as would have been the case if Japan had thrown its entire fleet into a single attack). While its capture would have made Japanese recon planes a problem, IIRC it wasn't anywhere near big enough to launch major air / naval attacks from (even water had to be imported). And as it was much closer to Hawaii than it was Japan it would have been much easier for the Americans to launch an invasion to retake the island that it would have been for the Japanese to keep it supplied.

Part of the reason why the USA could commit to Midway is they knew for a fact that at least some of the Japanese fleet was occupied elsewhere and unable to reinforce the fleet attacking Midway. IIRC through code breaking the Americans not only knew that Midway was the primary target, but also the relative strength of the fleet launched to attack it, the general direction the fleet was coming from and even the date. Even if they didn't know with 100% accuracy the forces they were facing with that kind of info the Americans knew that they could commit to Midway with a reasonable chance of success.

Had the Americans learned that Japan was putting their whole fleet into one group for Operation: "Giant Big Fleet Smash Midway!" IMO that would have given them serious pause and made them reconsider. Time was on America's side and if necessary they could have afforded to decline battle and lose Midway. Would it have stretched out the war? Sure, but probably not as much as losing 3 carriers to an overwhelming force in a battle that couldn't realistically been won.

I'm pretty sure Yamamoto would have known that as well which is why deception was a part of the Midway planning (though as you stated breaking up the fleet was also standard tactics). He kept his battleships in reserve hoping to catch the Americans by surprise and while in hindsight that was clearly a big mistake, given the circumstances and information he had I don't think that was a "temporary attack of insanity" on his part, as per the OP.

[Caiaphas]

Midway was an important base, but IIRC it wasn't critical enough for the USA to sacrifice 3 of its remaining carriers if they knew the odds of successfully repelling an invasion were overwhelmingly against them (as would have been the case if Japan had thrown its entire fleet into a single attack). While its capture would have made Japanese recon planes a problem, IIRC it wasn't anywhere near big enough to launch major air / naval attacks from (even water had to be imported). And as it was much closer to Hawaii than it was Japan it would have been much easier for the Americans to launch an invasion to retake the island that it would have been for the Japanese to keep it supplied.

Yeah, I made that statement before I got to the bit in Shattered Sword where they discuss how tiny the island was and how prohibitively difficult it would've been to turn it into anything resembling a useful base for the IJN. That and I did a quick look-see on Wikipedia, and apparently the Imperial Japanese didn't have any bombers at the time of the Midway attack that could've attacked Hawaii anyways (at least, they couldn't have made a round trip).

[Isolder74]

Part of the plan included the taking of the islands and bringing more planes to make into an extra unsinkable aircraft carrier and then pouncing on the American Carriers when they storm out to take the islands back. Something they tended to overlook was any outcome of war games they didn't turn out exactly how they planned. This included overruling several war games outcomes that resulted in losing 2 carriers to Midway based bombers. Much of the planning seemed victory fever had infected every member of the IJN leadership. For six months they'd gone from victory to victory without almost a single skip in the momentum. Their first real major setback was of course Coral Sea and even though they didn't consider it a major setback just a delay, as they'd assumed they'd get back on track once the Battle of Midway was won. Even after losing at Midway they didn't quit but still acted hoping they'd turn the tide back in their favor and it was only after the Guadacanal campaign that they lost almost all momentum.

[Tribble]

Just for your information, the Japanese didn't just assume that the Yorktown would be unavailable they'd assumed they sunk both the Yorktown and the Lexington at Coral Sea. It was only on the eve of the battle itself that they learned the Yorktown wasn't sunk but that's when they assumed it would be in the yard for at least a month just like the Saratoga was(forgetting how many system issue that poor ship had in the early war.)

Well then I stand corrected- Japan had originally believed the Yorktown had been outright destroyed, so they definitely weren't expecting more than 2 to show up at Midway.

[Isolder74]

The Yorktown was a ship that got listed as sunk by the Japanese several times including 3 times during the battle of Midway itself. Once as itself then as the Enterprise and finally as the Hornet(when the sub finally sunk it) so the Japanese went into the Guadacanal campaign assuming that they had at least left Midway at least somewhat even then oops Enterprise, Hornet, Wasp and Saratoga show up and they get extra aggressive again hoping to finish the job right this time. One of the reasons they sent their destroyers to the battle zone at Santa Cruiz, ending up finishing off the Hornet finally, was to make damn sure the ship they thought was sunk sure was this time.

They never did manage to do in plucky little Enterprise.

[Sea Skimmer]

I've yet to find time for a bit byu bit reply, but it is Waaaaaay off base to think the US would have ever refused battle at Midway. Midway-Johnston-Palmyra guard Hawaii, allowing Japan to take any of them unopposed was never happening, even if the US was even weaker. Taking any of these gives Japan a 1,000+ mile leap ahead, across an island free gap neither side could cross with land based air power. Midway couldn't sustain bombing of Hawaii no, but nor could any land based US planes have countered the Japanese on Midway. And as far as air capacity goes, Japan would run out of planes before it could fill up Easter-Sand and Kure islands. At MIdway the US had something like 130 planes around, a number limited only by the amount of apron space that had been constructed to that date.

The key thing about Nimitz knowing the Japanese objective was Midway was it let him concentrated US submarines and the limited pool of US land based air power at that island. Nimitz had expected an invasion of the island since the war began, and his main concern was that it might not be the next Japanese objective, not that he couldn't fight for it.

The Japanese battleships could not operate direcltry with the carriers, they are too slow and they need to conserve fuel. Japan could refuel its ships at sea, but not refill its tankers at sea, nor could the USN at this stage. For a US defense of Midway this was not abig deal, but for Japan with the whole fleet out it was a huge limitation. Total time at sea is limited, the more eocnomical crusing the better. Carrier task groups do not cruise economically, because they constantly have to turn into the wind for flight operations.

Also the slow Japanese battleship line was supposed to sail to a position well east of MIdway, about midpoint from that island and Adak in latitude (Adak was the original Japanese objective. The point of this force was clearly to cover the respective invasions against surface threats, it was hardly some grand deception operation. The fast battleships lagging behind the Japanese mobile force wit hthe carriers meanwhile had a similar objective no doubt around Midway itself. Since Japan could not replenish AVGAS or ordnance on its carriers it could not assure that these ships could defeat any quick US followup, battleships even low on fuel would be full of ammo and could do so for some days after the carriers would be useless. The pointers are pretty clear, and in line with prior Japanese operations. Deception was strategic here, not tactical. Japan was steaming right into US recon coverage, and the Midway invasion force steamed almost directly for the island from Saipan. As did the Mobile Force steam direct for Midway from Japan, followed by the battleships. The whole Japanese carrier force and battleships could plausibly have been spotted a day earlier, had it not been for a weather front the Japanese didn't plan on. That nerfed air search in the required sector, searches further south located the Midway invasion forces which commenced the battle.

[Caiaphas]

I've yet to find time for a bit byu bit reply, but it is Waaaaaay off base to think the US would have ever refused battle at Midway. Midway-Johnston-Palmyra guard Hawaii, allowing Japan to take any of them unopposed was never happening, even if the US was even weaker. Taking any of these gives Japan a 1,000+ mile leap ahead, across an island free gap neither side could cross with land based air power. Midway couldn't sustain bombing of Hawaii no, but nor could any land based US planes have countered the Japanese on Midway. And as far as air capacity goes, Japan would run out of planes before it could fill up Easter-Sand and Kure islands. At MIdway the US had something like 130 planes around, a number limited only by the amount of apron space that had been constructed to that date.

Wouldn't Midway be of extremely dubious strategic value to the Japanese thanks to its remoteness and the general weakness of Japanese logistics, though?

[Simon_Jester]

That still doesn't mean the US would give up the island without a fight. Among other things, I doubt they could assume they knew the full and precise extent of Japanese logistical capabilities.

[Isolder74]

Yammamoto hoped that he could at least capture the Hawaiian Islands or at least enough of them to hold hostage in negotiations with the US after the expected defeat of the US Carriers at Midway. He was hoping that without the carriers the US would be forced to pull their other heavy units out of Pearl Harbor back to the mainland US opening up a chance to seize some, or all, of Hawaii.

Logistics and resource issues were the main motivator with Japan wanting to seize as much of the pacific islands as they could just to ensure that they could be self sufficient enough to continue and finish their aims to control China gaining them further resources for the future. Often however they overlooked factors that made those gains useful to begin with. Capturing oil fields does you no good if you don't have a supply system in place to actually bring it home. They captured the lion's share of natural rubber plantations but also neglected shipping assets to actually use those resources. The list goes on not just with inbound but outbound supplies to their outposts. US Subs, carriers and land based aircraft continually sank or turned back cargo ships meaning resources and equipment quickly became truncated at their points of production.

Japan had supplies issues, manpower issues and production issues to the point by 1943 that both Truk and Rabaul were basically starving with even nearby fishing stocks depleted. Their Battleships and cruiser but for a few squadrons based in Japan itself were all based in Singapore and the Dutch East Indies because that's where the oil they need to run is. They are trying desperately to try and train replacement aircrews but can't because of how low the fuel supplies are becoming at the home islands making any training programs almost useless. That's '43 and it only got worse as the war progressed.

[Sea Skimmer]

The starvation problem was more 1944 then 1943, in 1943 forward postions like New Georgia and New Guinea were starving but not the big bases or anywhere in the Mandates. The invasion of Tarawa, collapse of Japanese air power around Rabaul (which sucked all the planes away that had been previously around Tarawa and ilk islands, plus the Japanese carrier air groups, again) and the raid on Truk though all came within a few months of each other late 1943-1944 and that's what utterly collapse Japanese shipping operations across the central Pacific. Rabaul IIRC never starved because so many supplies had reached it intended for Gaudacanal and New Guinea, and before that for operations against Samoa and Fiji; the Japanese could often land the troops from destroyers as it turned out, but not any supplies or equipment to follow.

Japan then tried to form a new defense line further west much more in line with its prewar strategic and operational doctrines, but the US smashed through the Mandates far too quickly and then, finally only then realizing its true strength advantage against Japan, against Japan, lunged right for the Marianas and shattered that idea.

Prior to that chain of events though Japan pretty well was supplying its military garrisons and keeping up a reasonable system, the problem was they were suddenly also trying to build up large land garrisons throughout the central Pacific, and that consumed oddles of shipping. All of this came at the expense of the civilian economy of course, but through all of 1942 Japan was only being tactically limited by allied power. They couldn't resupply Guadacanal, but they certainly could build up points close too it, allied power was too limited in actual deployed terms.

The US in hindsight could have been much more aggressive, but not at that much earlier a point simply because the massive mobile logistics force that supported the 1944 operations didn't exist yet. Its crazy, the US had 30 something repair ships supporting Task Force 58 and its planes and engines. Japan in contrast had literally one repair ship when the war began, and a second converted one. This let Truk had a small repair capacity.

Other then that Japan could only repair warships in the Home Islands, or at the captured facilities in Signapore, which is another reason why the went to Singapore besides the fuel situation. So once Truk was lost Japan was forced back strategically a massive distance.

Midway is not war winning, but its more important then a lot of atolls in the Pacific. As an air base and as a listening post, and while its isolated from other Japanese held land, logistically it is actually much closer to Tokyo (and thus all real Japanese power) then many islands in the Mandates. It also has a small protected port area, which few islands did, and since the US can't bomb it every single day they would have a hard time closing that to shipping until multiple Japanese wrecks actually block up the place.

if Japan took it the big deal is then the US has to take it back, we absolutely would have, and that would delay other more useful operations. But a lot depends on how long this takes, and how far developed the New Guinea campaign gets, as Japan will be able to much more heavily reinforce that area...but still launch it overland. The Japanese would never have tried another carrier assault in the Coral Sea, the allied land based power got too big too fast.

Japanese operations against Palmyra and Johnston would probably never happen, even if they somehow did make the ground attack on Midway actually work, but Howland and Baker island were still unoccupied by either side in mid 1942 and Japan might snap up those. It might also consider an operation against Canton island (which actually had thousands of Americans on it, Japan thought it was like 400 or something).

While the battle narratives have problems I still recommend Morrisons for the strategic background on a lot of this, and the US efforts to fortify all these remote outposts that never in the end, faced a Japanese assault. Many were completely empty when the war began, and while Midway had work done as early as 1869 on the shipping channel realistically nothing useful had happened for defenses or airfields before 1940. Nor had Japan really built up anywhere past basic airfield facilities. Japans whole plan was mobile land based planes would shift to whichever area of islands needed them, which was a good plan, and US carriers still feared this in 1943, but as it turned out Rabaul fighting had consumed most Japanese strength.

[Sea Skimmer]

Would anyone be interested in a KMZ file of the relevant mid 1942 situation? Including which islands were still unoccupied at that point, and a couple plausible (but not necessarily in Japanese Samoan delusions plans) locations Japan really could have taken following a major Midway victory?

[phred]

I would read the fuck out of that.

[Isolder74]

I probably already have but would love to have look at it.

[Tribble]

So, as per the OP, what do you think would have happened had the Japanese had combined their fleet to attack Midway? Assuming this also includes the fleet dispatched to take out the Aleutian islands? Would the USA have realistically been able to pull off a win?

[Isolder74]

Not likely. The inclusion of the heavy gun units would actually slow all of the carrier operations and give the Americans more chances to strike at them before they locate the American Carriers. Remember the Japanese are assuming that US Ships are not going to be in the Midway Islands area at the outset of the battle. Once it is realized that American Carriers aren't living up to plan the same confusion from the real battle would set in. Adding the Aleutian units would only add one small carrier to the Japanese side which would not add much to the overall capability of the Japanese carriers.

[Sea Skimmer]

The problem remains the lack of troops to actually take the island, and as the Japanese never had much bombardment ammunition, or ammo at all frankly, and would have wanted to be ready for a surface action adding lots of ships doesn't add much firepower for land attack in the terms Japan operated. If the Aleutians invasion force was also added and actually made an assault alongside the other troops (only half of whom were even to be an assault force, the rest were like aircraft mechanics and AA gunners) the Japanese odds of actually taking the islands would go way up, but since Japan plainly learned nothing from Wake and had poor intelligence their would be no real reason for them to do this.

THe Aleutions force had two carriers though, its about like adding another fleet carrier to the battle, and more importantly another independent task force. The Japanese would certainly win the naval battle, the Japanese had several other CVLs in play too after all, but an occupation of the islands would kinda remain in doubt.

Japanese advantages like superior range of plane would also remain very difficult to exploit, and Japanese ASW remains pathetic, and while the Mk14 torpedo doesn't really work the Mk10 sure did and a lot of US submarines were in the area/

[Sea Skimmer]

Well I have enough of a KMZ made that it's worth looking at, but I'm not sure how to host it at the moment so if anyone wants an early look drop me a PM to get an email preview.