I’m sure it would have made A difference, but how much? Japan continued knocking out Allied fleets and aircraft for months after Pearl Harbor with hardly any losses, even when the forces were relatively even. This was especially the case in air battles in the Philippines and sea battles in the Dutch East Indies.
The US Navy had yet to learn the lessons of providing sufficient air cover over their surface fleets, and if the fleet had sailed it would have faced to prospect of being sunk in deep waters where they couldn’t be re-floated and salvaged.
Had the US fleet run away to the East, the battleships would probably have survived, but they wouldn’t have been of much help in the coming months. Plus, they wouldn’t done that – it would have been seen as cowardice rather than prudence.
In fact the only reason I think several weeks rather than days might have made a bigger difference is that it would have allowed time to ferry hundreds of more planes to the islands, perhaps enough to blunt the attack.
I was going to do the same thing. And that idiot McClellan still couldn’t beat Lee.
I’m not sure it would make much difference, except maybe the carriers would get sunk as well and the battleships would be sunk in deep water and unsalvageable.
Yeah, that’s a good one. The American Revolution fairly easily could have failed, and the world could vary from not very different at all (was it inevitable that Britain’s North American colonies would break away, even if 20 years later?) to insanely different (assume that every event in which the USA was a player in the past two centuries didn’t happen…).
That was the battle where, according to the story, the Hessian commander was given a note warning of the attack the night before by a Loyalist, but he shoved it in his pocket without bothering to read it and continued playing cards. So this wouldn’t be a case of leaking plans so much as it’d be putting “IMPORTANT! PLZ READ!” on plans already leaked.
Never mind that – just give McClellan some bad potato salad. He had the battle plans and enough time to execute them; the issue was he wasted the time hesitating. With McClellan hors de combat, even his sycophantic subordinates might have managed to catch Lee before Lee concentrated. Instead of a Battle of Antietam, you’d have three or more smaller battles scattered about the Maryland/Pennsylvania border as the Union mopped up.
Just to be old school, I’ll nominate telling Vercingetorix that Caesar planned to follow him and lay siege to Alesia. Maybe he wouldn’t hole up there and get trapped.
Just to get all recent, the 9/11/2001 attacks. If the Bush Administration had known what was coming, prevented the attacks, and rounded up the 9/11 terrorists, they would have been big damn heroes for a season, but it wouldn’t have enabled them to get us involved in two interminable wars and grossly expand the national security state.
But we’d still feel secure, so no additional security would be done. The next attack would probably succeed since Al Queda would still be flourishing. There’s no reason to think 9/11 was a one shot deal. Even if it totally failed, they’d keep trying.
The follow up attack that finally succeeded could actually be much worse. Think about how bad the reaction would have been if they nuked a city.
Roosevelt already had all the plans, and he purposely kept the Army and Navy in the dark. Didn’t you know?
(Who was that? Wasn’t there a poster who was arguing that? Or did I see that on another board?)
I don’t think so.
If the US knew the Japanese plans to the level specified in the OP, it would have been a complete game changer.
Given the premise of the OP, that the side would have enough time to react meaningfully, it would allow the US to bring in more aircraft. They already had 87 P-40 B and 12 P-40 C as well as 39 P-36 A. Not that I would want to be a P-36 pilot against a Zero, but the more in the air the better.
Even with just the planes in the Pacific, they could have destroyed the Japanese, and with time, they could have brought in some of the carriers from the Atlantic fleet and more aircraft from the mainland.
The Japanese launched their planes at 6:00 am. Having a US attack schedule at 5:45 would have caught them by complete surprise. It may be possible to have located the fleet in the predawn hours. Certainly knowing the intended launch area would have allowed the US to be looking in the right direction and could have flooded the area with aircraft, destroyers and subs looking for the fleet.
With pre-catapult carriers, it took the Japanese over an hour to launch all of their planes. USAAF and USN planes would have caught the Japanese with full decks of planes, bombs and fuel. It would have been a bloodbath.
The entire Kidobutai fleet would have been wiped out. Even if the Japanese got a few planes up, or even more than a few, the battleships would have been OK. They would have had air cover which would have devastated the torpedo bombers. The level bombers with the modified AP bomber would never had been able to hit their targets. Dive bombers were worthless against the armor on BB.
With the six best carriers gone, and the remaining four – more like escort carriers or quite a bit older – the Japanese would not have gotten free reign of the Pacific.
Worse for them, if the US knew the attack plans on Pearl Harbor, they would have known that PI and other bases were going to be hit. With that much warning, even Dugout Doug would have been prepared and not have been required to have obtained that moniker.
Although this wouldn’t have helped the Chinese, the other members of the ABCD alliance would have been better prepared. The DEI, Malay, Hong Kong and Singapore could easily have been saved. The Prince of Wales would have already been in Singapore under precious air cover.
Without her fleet, no land and no oil, it would have been game over.
How about Dunkirk? In the week or so after the decision to withdraw, the British saved over 300,000 British and Allied soldiers. How much would that have changed the war?
A huge game-changer would be if the Russians knew about the trap in the Battle of Tsushima. Two-thirds of the Russian fleet was wiped out and the Japanese won the war. Had it gone the other way, I believe that the Japanese would not have gone down the path of ultanationism which directly led to WWII.
It certainly would have completely changed Japanese navel doctrine.
Another possibility would be the Battle of Manila Bay in the Spanish-American war. Had the Spanish been able to defeat the US forces, it’s possible that the US would have settled for the rest of Spain colonies.
Had PI not become a US colony, and won independence from Spain, the US may not have had the same ties and military presence. Japan could have attacked it in WWII without having to first take out the US fleet. Actually, the US would not have transferred the Pacific fleet to Hawaii in the first place.
PS - when I wrote lives saved, I really did mean both sides. Three years avoided; the farm-by-farm devastation averted, reconstruction considerably lessened because of devastation averted. Entire cities saved.
The idea wasn’t born of some Jedi vs Empire mindset*, but that in the beginning and in the end, we all were and are Americans.
*granted, Natalie Portman in Cold Mountain? Very hot.
