With complete foresight, what would have been the least costly way of ending the Pacific War (WW2)?

From a purely statistic point of view and knowing exactly when and how the war ended, could World War 2 in the Pacific have been won by simply just waiting out/ignoring the Japanese until the atomic bombs were done, then just sending them into Japan from bases in China? No need to actually land or invade anywhere besides naval patrolling near Allied bases to prevent any more surprise attacks?

Speaking from the Allied side BTW, so I’m also including Chinese and British Commonwealth losses in this tabulation. Also you can’t just ceasefire it early-on, it has to be the same unconditional surrender as in real life.

if the Japanese conduct had been better especially in the Philippines and china we might of just ignored them …

What really screwed them was Pearl Harbor. Strategically, there was no way for Japan to win. None. Even in an alternate universe where everything went wrong for the USA, where the U.S. lost a the next dozen naval battles, lost Hawaii, even started getting bombed on the West Coast, the USA’s victory was inevitable.

The USA had a whole additional coast and system well out of any conceivable attack by Japan. It had a vast population, clearly no trouble getting millions of them to sign up to fight, and just dwarfed Japan in every conceivable metric.

Battles may be won by General rank officers, but a war gets won or lost based on these kinds of numbers.

So if they hadn’t attacked in Pearl Harbor or other U.S. possessions, and had behaved better, things would have gone very differently. I could still see a war, but a more limited one, fighting over some U.S. possessions and ending in a treaty, similar to the Spanish-American war.

You couldn’t have ‘just’ ignored them and then dropped atom bombs on them: bomber range was only possible after closer air-bases were captured, and the actual bombing raid took place after air-defence was defeated.

On the other hand, in retrospect, the whole Papua/New Guniea campaign was a waste of effort. The Japanese were defeated in that theatre by naval losses and starvation.

Without wishing to change the subject, an equally interesting question is “in retrospect, what would have been the effect if the USA had committed to defeating Japan, instead of waiting until the European war was finished?”

This is not true. Remember the Doolittle Raid? Better aircraft for that type of bombing could have been developed, launched purely from a carrier task group. If the major fighting had taken place 6 months the surrender of Japan in the main history, the U.S. would have had at least a dozen nuclear devices. If it could get 10 hits on Japanese cities with them, I think it would start a death spiral. Where the U.S. sends out fleets, fights with Japan in the open seas, supplied by ships, and fights to close enough to the coastline of Japan to kill some cities.

Gradually, as more and more of Japan gets turned into mushroom clouds, the Japanese ability to resist would have diminished accordingly. All their other islands they took would be irrelevant if the mainland factories that supply their war machine with weapons…and their civilians with essentials…ultimately all get nuked.

This is perhaps a naïve question; but if you have perfect foresight, couldn’t you just sail the US fleet out of Pearl Harbor to meet the Japanese First Air Fleet in late November 1941?

The least costly way of ending the Pacific War (WW2), with complete foresight, would be to have joined with Germany during the first World War … with a more prosperous Germany in the 1920’s we’ll not see the Nazis rise to power during the Great Depression … without a European theater of war the USA would be more inclined to continue trade with Japan during the Sino-Japanese war, keeping in mind Germany controls what is today Indonesia …

But that’s not what the OP is asking … and I’ll go ahead and say the USA did use the least costly way to end the Pacific War … “If it could get 10 hits on Japanese cities with them, I think it would start a death spiral.”; well that’s pretty much what the USA did do, except the Japanese surrendered after the first two bombs …

With complete foresight, then we would have known neither Germany nor Japan was trying to develop nuclear weapons … then we could have saved money by skipping the Manhattan Project … come August 6th, 1945, the USA just lets the Red Army invade the Japanese home islands … with the USSR all tired and beat up the USA sends Patton and his tanks to the Urals … easy peasy …

With complete foresight then it might have been better to occupy Berlin in WW1, as per Pershings advice who had noted that Germans would only understand their defeat if the whole country had been filled with allied troops. This would have destroyed the myth that Germany had been betrayed by a civilian administration and in particular that the Jews had done the betraying - without which Germany would have won.

IIRC the Japanese had 6 carriers in their strike force, while the US fleet had only two in Hawaiian waters in late 1941.

The least costly way to end the war would have been for the 21st Air Command to focus on the Japanese transportation network, bombing railways andmining harbors, rather than fire-bombing Japanese cities. The latter caused great damage to civilians, but less to the Japanese.

Since this requires speculation, let’s move it to IMHO.

Colibri
General Questions Moderator

  1. That’s true. It’s very much in doubt whether the USN would have been better off if the whole US force around Hawaii had met the Japanese striking force at sea rather than the actual outcome of serious losses to the battleships but the carriers avoiding contact. Although to be fair depending the degree of foresight one might assume more than Lexington and Enterprise could have been near Hawaii. Saratoga was on the west coast, through Ranger, Yorktown and Wasp were in the Atlantic. Hornet had recently been commissioned but was not nearly operational.

  2. That might be true at the margin, but there was already a large and by March 1945 (the start of big night fire raids*) largely successful campaign of attacking Japanese shipping by submarine (and eventually quite effectively by a/c based in China and PI too), besides lots of attacks on Japanese railroads where it really mattered in the occupied territories on the Asian mainland. The function of railways within Japan made less of a difference with imports brought to a virtual standstill. And the B-29 mining campaign got into full swing within a pretty short time later in the big picture; that campaign, air units from Okinawa and mine detecting sonar equipped submarines cut off the last route to Japan from outside, via Korea across the Sea of Japan which submarines previously couldn’t get at**.

Seems all in all this point would mainly relate to the common (though basically anachronistic IMO) debate of the ethics of the fire campaign rather than a way to have shortened the war appreciably.

*there were earlier area fire raids by B-29’s but not as large and/or in daylight, besides HE raids.
**again with a few earlier exceptions

Remember also that there was a great shortage of modern carrier aircraft. Much is made of how obsolete the Devastator was at Midway, but the Hornet at least had SBC Helldivers (a biplane design) until some point in 1942.

Not really. The importance of attacking railroads was mostly to inhibit food shipments. Starving workers seems more effective than dehousing them. But I made a mistake of focusing on 21st Air Command. All of the Pacific air commands should have focused more on mining. It wasn’t as though the B-29 was the only bomber that could carry mines, and aerial mining was a much cheaper antishipping weapon (both in US lives and money) than the submarine campaign.

Completely unrealistic. The B-25 bombers Doolittle flew had a maximum payload of 3,000 lbs. The Little Boy bomb weighed 9,700 lbs. and the Fat Man weighed 10,300. Even the B-29 had to be specially modified to carry them.

Um, I think we did choose the least costly way of ending the war in the Pacific even without the foresight. It’s not like we developed the A-bombs for use on Japan, we already had them.

Well, barely.

The first atomic bomb test was Aug 16, 1945. It was 22 days later when the bomb was dropped on Hiroshima.

With hindsight, we could have trained, from the beginning, in the “corkscrew and blowtorch” tactics which, in history, had to be learned from scratch, and the hard way. We’d know, going in, how tough island-hopping would be, and we could be better prepared for it.

We’d know more about how effective (or not) torpedo bombers were, and maybe put more emphasis on dive bombers. We wouldn’t make the same mistakes we made with badly-engineered torpedos, etc.

This is all small potatoes, but enough small potatoes win wars. This kind of “miracle” fore-knowledge would allow us to fight the same battles with significantly fewer casualties.

(More Navajo code-talkers!)

(Heck, what with code-breaking and all, we had an almost miraculous level of fore-knowledge!)

Considering the battles for Iwo Jima and Okinawa were both done mainly as staging grounds for an invasion of Japan that never came to pass, in hindsight they both seem like they were done for ultimately nothing.

Similarly the entire New Guinea campaign was mainly to prevent Japanese offensive operations towards Australia and other nearby areas, but it seems like the US could have easily by-passed it and focused solely on securing the Central Pacific.

Ok, yes, as mentioned above the bomb wasn’t available for most of that time. Once it was available we quickly changed strategy. I don’t know enough to say if what we were planning months before was optimal. With enough foresight it does sound like we could have avoided many casualties and great cost with some other plan.

If the Americans had never blockaded shipping of oil to Japan, and had never stationed our entire Pacific fleet in an aggressive posture in the middle of an ocean to which Japan had equal rights to access and influence, things might have been different.

A curious sentiment, given your location. Japan had been romping around in China since July 1937, and Indochina since September 1940 which is what led to the oil and steel embargoes and moving the fleet to Hawaii in the first place.

Wiki:

Do you really think that had the allies not done so, the Philippines would not have been sucked into the Greater East Asia Co-Prosperity Sphere, eventually if not in December 1941?