US initiates war with Japan?

I don't think so. FDR wanted to get the US into ww2 for awhile before that, but he knew the political cost couldn't be paid without something that would enrage Americans, like being attacked on their own soil.
 
Given American constitutional law, not a chance. When FDR asks for a Declaration of War would be a big clue for the Japanese
 
Maybe. Japan had finalized their war plans for the Southern Resource Area and initial attacks on the Philippines and Pearl Harbor by November. If the US received incontrovertible intelligence of Japanese intentions at that time, it might spur Roosevelt to get his licks in first, using the Japanese war plans as a casus belli. It's probably more likely that the Philippines and Hawai'i are alerted and prepared as much as possible and Japan is still allowed to strike the first blow, though.
 
Is it at all plausible for the US to attack Japan first, around the time of OTL pearl harbour?

U.S.S. ENTERPRISE

November 28, 1941
BATTLE ORDER NUMBER ONE
1. The ENTERPRISE is now operating under war conditions.

2. At any time, day or night, we must be ready for instant action.

3. Hostile submarines may be encountered.

4. The importance of every officer and man being specially alert and vigilant while on watch at his battle station must be fully realized by all hands.

5. The failure of one man to carry out his assigned task promptly, particularly the lookouts, those manning the batteries, and all those on watch on the deck, might
result in great loss of life and even loss of the ship.

6. The Captain is confident all hands will prove equal to any emergency that may develop.

7. It is part of the tradition of our Navy that, when put to the test, all hands keep cool, keep their heads, and FIGHT.

8. Steady nerves and stout hearts are needed now.

G. D. MURRAY,
Captain, U.S. Navy
Commanding
Approved: November 28, 1941.
W. F. HALSEY,
Vice Admiral, U.S. Navy,
Commander Aircraft, Battle Force
 
Had Japan not bothered with Pearl Harbor and had the US detected an invasion convoy approaching the Philippines, then they would have shot first and asked questions later. Likewise if they'd discovered the KB off Hawaii.

Well, they might have asked a few questions first actually - "Such as WTF are you doing here?" followed by "Turn around and go home immediately". Which would have been ignored, and AIUI Congress is needed to declare a state of war, not to take military action - by which point it would have been obvious to everyone that there was a war going on whether Congress liked it or not.
 
Maybe. Japan had finalized their war plans for the Southern Resource Area and initial attacks on the Philippines and Pearl Harbor by November. If the US received incontrovertible intelligence of Japanese intentions at that time, it might spur Roosevelt to get his licks in first, using the Japanese war plans as a casus belli. It's probably more likely that the Philippines and Hawai'i are alerted and prepared as much as possible and Japan is still allowed to strike the first blow, though.
Japan being allowed to start the war how they like, with time and location that works best for them, seems foolish to me.

Any idea how the US would initiate the Pacific war if it could? None of the Japanese islands seem quite as exposed as Hawaii.

Perhaps a large force is sent to the Philippines, which attempts to keep the Japanese north and east of Taiwan?
 
Japan being allowed to start the war how they like, with time and location that works best for them, seems foolish to me.

Any idea how the US would initiate the Pacific war if it could? None of the Japanese islands seem quite as exposed as Hawaii.

Perhaps a large force is sent to the Philippines, which attempts to keep the Japanese north and east of Taiwan?
US wants to delay a Pacific war as much as possible, it starting in 1944 would be ideal for them, as the heavies from the Two Ocean Navy would start showing up then. However every bit of delay means US islands are better fortified with more troops stood up, delay works for the US

US warplans called for letting Japan take the offensive until the fleet train is large enough to support large scale offensive ops, this would be 1943. US Navy had considered the Phillippines impossible to defend for a long time

Only way the US would start the war, was if they knew Japanese plans and could say ambush the Kido Butai at sea near Hawaii with everything they have, and the President could prove to the American people conclusively what the Japanese were doing
 

ben0628

Banned
Have the US go to war with Germany first, leading to an eventual declaration of war on their Asian ally?
 
Japan being allowed to start the war how they like, with time and location that works best for them, seems foolish to me.

Any idea how the US would initiate the Pacific war if it could? None of the Japanese islands seem quite as exposed as Hawaii.

Perhaps a large force is sent to the Philippines, which attempts to keep the Japanese north and east of Taiwan?

In this scenario, it's a matter of when the US gets wind of Japanese intentions. In November, with less than a month until Pearl Harbor, is too little time to plan an offensive operation of their own from scratch, put together a logistics train, and stage forward to the Philippines. They may instead try to intercept the Kido Butai on the high seas en route to Hawai'i, but a direct attack on Japanese territory a la Pearl Harbor is too ambitious for the USN at this point.

Edited for clarity and grammar
 
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Is it at all plausible for the US to attack Japan first, around the time of OTL pearl harbour?
If Japan attacks Malaya and DEI and invades the British and Dutch islands throughout the below map, I think the US will be pressed to war, though not immediately. The US would not sit by whilst the Philippines were surrounded.

pbohZG2jTsKbjLsw7XSS
 
In this scenario, it's a matter of when the US gets wind of Japanese intentions. In November, with less than a month until Pearl Harbor, may be too little time to plan an offensive operation of their own, put together a logistics train, and stage forward to the Philippines. They may instead try to intercept the Kido Butai on the high seas en route to Hawai'i, but I think a direct attack on Japanese territory a la Pearl Harbor is to ambitious for the USN at this point.

So; 1941: the US luckily intercepts some communications, finds clear proof the Japanese intend war, and intend a surprise decisive battle with the US in the Pacific. They begin preparing for war earlier and more urgently, including determing the details of the attack by spying or guesswork. In the first days of December a US fleet ambushes the Japanese north west of Hawaii, and a battle something like midway takes place, where Japan looses all 6 carriers with the US loosing 1 and 1 being very heavily damaged.

How much would this change the war? I've found a few threads on what if Pearl Harbour went worse for the Japanese / better for the Americans, but nothing quite like this.
 
So; 1941: the US luckily intercepts some communications, finds clear proof the Japanese intend war.... In the first days of December a US fleet ambushes the Japanese north west of Hawaii, and a battle something like midway takes place, where Japan looses ....

How much would this change the war? I've found a few threads on what if Pearl Harbour went worse for the Japanese / better for the Americans, but nothing quite like this.

The Navy might be ready to negotiate, but the Army would veto this and require months or years to accept reality.
 
In this scenario, it's a matter of when the US gets wind of Japanese intentions. In November, with less than a month until Pearl Harbor, may be too little time to plan an offensive operation of their own, put together a logistics train, and stage forward to the Philippines. They may instead try to intercept the Kido Butai on the high seas en route to Hawai'i, but I think a direct attack on Japanese territory a la Pearl Harbor is too ambitious for the USN at this point.

Neither the previous War Plan Orange, the Successor Rainbow plans, & the Pacific Fleet plans (ie: WPP-46) proposed more than raids and small opportunistic operations in the first 12 to 18 months, or mid 1943. During the 1920s & 30s fleet exercises and map exercises had repeatedly shown trying to charge off to the Phillipines prematurely was a losing proposition.
 
Neither the previous War Plan Orange, the Successor Rainbow plans, & the Pacific Fleet plans (ie: WPP-46) proposed more than raids and small opportunistic operations in the first 12 to 18 months, or mid 1943. During the 1920s & 30s fleet exercises and map exercises had repeatedly shown trying to charge off to the Phillipines prematurely was a losing proposition.

Good point. American prewar planning always envisioned a defensive phase at the outset of any potential conflict because it was assumed that a Pacific War would be kicked off by Japanese aggression. The idea of putting the USN battle line to use with a preemptive attack would be anathema to all prewar doctrine, nor would there be any planning or logistical groundwork previously in place.
 
If Japan attacks Malaya and DEI and invades the British and Dutch islands throughout the below map, I think the US will be pressed to war, though not immediately. The US would not sit by whilst the Philippines were surrounded.

pbohZG2jTsKbjLsw7XSS

I think other users have commented in the past that Japan only targeting the British and the Dutch would lead to the Americans enforcing a very one sided neutrality, especially in the Pacific, and I am tempted to agree. All while they have adopted a war economy and are reinforcing the Phillipines, Wake and Guam as fast as possible. Eventually the Americans would poke the Japanese enough that war might break out in April 1942, with the Americans holding a knife on the Japanese artery between Japan and South East Asia. If war broke out by accident on the part of the Japanese, they could expect a few weeks of pain in the South China Sea which might cause serious delays in the capture of the Malay Barrier.
 

SsgtC

Banned
In the first days of December a US fleet ambushes the Japanese north west of Hawaii, and a battle something like midway takes place, where Japan looses all 6 carriers with the US loosing 1 and 1 being very heavily damaged.

Never happen. The USN had only 3 carriers in the Pacific in December 41 (Lexington, Saratoga and Enterprise). Even if you postpone Saratoga's refit and have all 3 decks available, the USN did not concentrate their carriers together. The IJN did. I think you're more likely to see two US carriers sunk with a third heavily damaged and maybe one IJN carrier sunk with one damaged. The only way the USN carrier force inflicts crippling damage on the IJN is if they catch the carriers immediately after recovering a strike and in the middle of refueling and rearming operations.
 
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