> If you play "what if" and imagine the Japanese had won Midway, and the US had no carriers at all, that gives the Japanese total control of the Pacific. The Japanese can take Hawaii if they want to, because how could the US possibly reinforce and resupply it? The Japanese can attack shipyards and ports on the West Coast at their leisure - and those would be defended obviously, but the attacks would greatly slow the progress of shipbuilding.

So here's the big problem with that thesis: the attacks at Pearl Harbor and Midway stretched the IJN's supply and logistical capabilities to their utmost limits. It's very likely that in any actual attempt to take Pearl Harbor, the US would have sabotaged the port facilities to the point that it would have required months, if not years [1], to bring it back up to an operational status capable of being used as a forward operating base for striking the US West Coast. Oh, and this is Hawaii--everything has to be brought in from the mainland, which means you're diverting a lot of shipping to maintain a supply line while you're repairing the harbor at the same time. Which is going to be vulnerable to submarine activity the entire time, and Japanese anti-submarine practices were terrible.

Yes, Hawaii is the strategic linchpin of the Pacific Ocean. However, it is so remote that actually acquiring strategic control is extremely challenging. At the same time, Japan is basically running against the clock: the Essex carriers start commissioning at the beginning of 1943, and that's the countdown Japan is running against. Japan just doesn't have the time to consolidate Pearl Harbor into an advance operating base, even if it could theoretically capture it.

[1] Keep in mind that the US was still in the middle of upgrading Pearl Harbor to serve as Pacific Fleet anchorage, which was I believe a decade-long process.

From what I've read, Japan never had anywhere near the industrial capability to pull any of that off. Even landing troops and maintaining a garrison at all on Midway and the Hawaiian islands would stretch them to the limit - they arguably already didn't have the troops to spare to do that along with their other commitments in their Greater East Asian Co-Prosperity Sphere plan.

Taking Hawaii at all is already outlandish, no chance that if they found a way to pull that off, they'd be able to supply it heavily enough to make it an active seaport, patrol the waters to the east aggressively, or carry out attacks against the US West Coast and their land-based defenses at a high enough tempo to impede shipbuilding there. Similarly, maintaining enough spies and subs to track ship sorties and ambushing them at the Panama Canal isn't in the cards for them.

WWII is ultimately a logistics war. Individual battles don't really matter that much, whoever makes the most stuff will win eventually somehow, and whoever is on the other side from them will lose. Japan was way too far behind on industrial capacity to have a chance. Maybe if they managed to pull off their Co-Prosperity Sphere plan without any interference and make the most of it, they'd have the capacity in 40 years. But that's doubtful too, since everyone else in their so-called Co-Prosperity Sphere hated their guts due to horrible occupation practices on the part of the IJA.

Yes Japan has almost no natural resources which is why they invaded Asian countries in the first place. But allied submarines and seaplanes were hammering their supply lines constantly to the point they could barely get anything shipped to Japan.

The war was a Japanese gamble and quite a few intelligent Japanese predicted it would fail.

That's the reason behind why Japan invaded Manchuria in 1931. Japan's invasion of the rest of China though was an act of militaristic hubris that caused a net loss in resources over 4 years and led them to invade the rest of southeast asia to patch this hemorrhage which then drew the US into the conflict with its oil embargo.

Japanese military planners in 1937 knew an invasion of China would be a waste of precious resources for little potential gain. But they were sidelined by younger military officers that wanted a shot at battlefield glory and ignored orders from above for a ceasefire after the Marco Polo bridge incident. And after the first battlefield victories started rolling in it became politically impossible to halt the momentum for continued war.

I don't understand how you could question American ability to resupply Hawaii but not Japan's, given the fact that the core point is that the IJN could not afford the losses which they were suffering throughout Pacific War while the US could. The supply lines that the IJN would need to reach out so far would have given American forces the overwhelming home field advantage while greatly diminishing the capabilities of the IJN. Conversely it was no accident that the US still endured terrible losses in spite of it's overwhelming numeric advantages. The amount of manpower and material required for such long distant campaigns is enormous, and it's no accident that Super Powers are defined by their ability to wage war far away from home.

> I don't understand how you could question American ability to resupply Hawaii but not Japan's

I'm claiming that if one side has a carrier and the other side doesn't, that will determine who can reliably move convoys across the pacific.

The carriers have such an enormous capacity for reconnaissance, it's hard for me to imagine a convoy sneaking past them. So if Japan has a carrier dedicated to the blockade of Hawaii, it seems to me that Hawaii is effectively cut off.

By contrast, the US would attempt to interdict Japanese supply convoys by using the only tool they'd have left: submarines. Better than nothing, to be sure. But it's much more difficult for a sub to find a convoy, than it is for multiple airplanes.

That is not how convoys work.

You're proposing using capital ships--ships of which even the largest numbers had single digit numbers--to escort convoys. This takes them out of the action for any other offensive or defensive naval operation you might want to use. Instead, you'd use destroyers (of which you have hundreds) and cruisers (merely dozens). This also lets you have several escort vessels per convoy, which is superior because two ships can be in two places at once which a single ship cannot.

> By contrast, the US would attempt to interdict Japanese supply convoys by using the only tool they'd have left: submarines. Better than nothing, to be sure. But it's much more difficult for a sub to find a convoy, than it is for multiple airplanes.

... Merchant and convoy raiding by WW2 existed almost exclusively of submarines attacking convoys. The Germans did attempt using surface ships to raid convoys, but their record was absolutely abysmal, and it's pretty universally agreed among naval historians that not building those ships would have been better for Germany.

Now, in 1942, the US submarine fleet was greatly hampered by the fact that the Mark 14 torpedo was a piece of shit that didn't work, and the Bureau of Ordinance refused to countenance those claims. However, the US was historically targeting Japanese shipping with submarines the entire time, and once the Mark 14 torpedo was finally fixed, the US submarine fleet would go on to be the most successful of WW2, having sunk virtually the entire Japanese shipping fleet.

There's even more considerations that I'm not including here, but hopefully this should be enough to convince you that figuring fleet carrier numbers are not going to determine the victor of a battle for merchant shipping.

> You're proposing using capital ships--ships of which even the largest numbers had single digit numbers--to escort convoys. This takes them out of the action for any other offensive or defensive naval operation you might want to use. Instead, you'd use destroyers (of which you have hundreds) and cruisers (merely dozens). This also lets you have several escort vessels per convoy, which is superior because two ships can be in two places at once which a single ship cannot.

The Allies (mostly the US) built lots of escort carriers, precisely for escorting convoys (be it "normal" convoys or invasion fleets in the Pacific), and AFAIK they were considered pretty successful and took some of the glory of winning the battle of the Atlantic. But yeah, you can, with some justification, argue that escort carriers aren't capital ships.

> The Germans did attempt using surface ships to raid convoys, but their record was absolutely abysmal

IIRC the German auxiliary cruisers (HilfsKreuzer) were considered pretty successful, as they were cheap and since they were just converted merchant ships with guns etc. hidden they could often get quite close to a target before revealing themselves. But these were used for picking off lone merchantmen, not convoys.

> it's pretty universally agreed among naval historians that not building those ships would have been better for Germany.

Yes, the German capital ships were an almost complete waste of resources. Those resources would have been much better spent on, say, u-boats and land-based aircraft. I guess the only positive return Germany got from them was as a sort of 'fleet in being', in that their mere existence forced the allies to commit their own capital ships to the area in case they turned up to attack some convoy.

Of course, had the Germans not built their own capital ships, the Allies would have also reacted, e.g. by not building or stationing their own capital ships in the area, and spending more resources on, say, anti-submarine efforts. So I'm not certain the battle of the Atlantic would have turned out any different in this case either, just even more bloody.

Hawaii is an unsinkable carrier itself. If the US lost its carriers at Midway, Oahu would have been host to a massive force of fighters and long distance bombers.

Any Japanese fleet unlucky enough to come within five hundred miles of Oahu would be subject to an unending stream of heavy US bombers like the B17 escorted by long range fighters such as the P-38.

There would be little chance of any surprise either with radar installations far improved and a vigilant picket line of US subs.

Landing troops without air superiority would have been impossible, and it’s unclear whether a Japanese carrier fleet could even hold off US battle ships if they sailed with US air cover.

To win that parley, land troops and push a large US Army force off Oahu is almost impossible. But even then, to raid the US coast with your remaining fleet, against an even more formidable air and sea defense many thousands of miles from any resupply would be a disaster for the Japanese Navy.