# What if the Japanese fleet had been destroyed on Dec 6th 1941? **URL:** \ **Category:** Great Debates\ **Created:** [September 15, 2012, 5:35pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802 "2012-09-15T17:35:23Z")\ **Posts on this page:** 13\ **Page:** 3
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [September 18, 2012, 5:30am UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/41 "2012-09-18T05:30:14Z")
Remember **Boyo Jim** , the hypothetical here in the OP is if the Japanese fleet had been destroyed, I would think that we should concentrate here with the scenario that assumes that the Americans were well prepared and with planes and bombers already on alert and on the air sinking Japanese aircraft carriers with better intelligence than was used that day and with the same incredible luck that was used for real in the decisive battle of Midway. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [September 18, 2012, 6:49am UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/42 "2012-09-18T06:49:02Z")
> [@Sailboat](#): > > Eh. I linked to that declaration in my post you’re picking for nits. And I did not say the “14-part message” was a declaration of war. What I was trying to say (without having anything solid enough to cite) is that a declaration by Japan was essentially inevitable at that point (unless, I suppose, they made some frantic last-second attempt to stop the process because of the hypothetical in the OP, but I find that implausible). My apologies to you, Saint Cad and smiling bandit for misreading/misinterpreting what was written; my only defense is lack of sufficient caffeine in my system when writing this morning. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [September 18, 2012, 12:05pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/43 "2012-09-18T12:05:36Z")
> [@TokyoBayer](#): > > Again, you are making an assumption that the US found out at the last moment with no ability to change what it did. That’s OK, but you have to recognize that you are placing an arbitrary constraint. … Actually, no, assuming _cckerberos_ is correct that the Japanese made the final “go” decision on December 2, then I was giving the American fleet the maximum available time – the same amount of time as the Japanese fleet had before the attack was launched. I don’t see any other reasonable way to guesstimate how much advance warning the Americans could get. I asked in an earlier post how much advance warning there was, and got no response. But I’m realizing I’m hijacking this thread with my skepticism over the possibility of OP happening, so I will stop. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [September 18, 2012, 1:29pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/44 "2012-09-18T13:29:06Z")
> [@Boyo\_Jim](#): > > [According to this page](http://www.history.navy.mil/faqs/faq66-9.htm), America could have had two carriers (Enterprise and Lexington) at Pearl Harbor with 5 days notice. (. . .) The remaining carriers were also all in the Atlantic – the Yorktown, Wasp, and Ranger --none within range to get to Hawaii in time. :dubious: I addressed this in my previous post, but if you have previous intel, what military justification is there for waiting until the enemy was made a formal decision to start preparations? If that’s the case, why would they have taken any defensive steps until Japan actually dropped the first bomb, since they may not carry though? According to match a scenario in the OP, the US would have gotten the information on the attack. It does not specify that the information would have come only _after_ the formal decision was made by Hirohito. > [@](#): > > Honestly, the American defeat at Pearl Harbor would have been even worse if the Americans began preparing for the attack on December 2, than the surprise attack actually was. This arbitrary constrain simply does not make sense. Even if one were to take your constraints, the US has a large force. > [@](#): > > Had this happened it would have been a far more even battle, as America did have a couple of hundred (pretty much obsolete) fighters it could put up as a defense. Did you read your own cite? How was the P40-B fighter “obsolete?” There were 87 of them. There were another 39 P-36. > [@](#): > > Five of 39 in training unit flew at Pearl Harbor, credited with two zeros in addition to 11 brand spanking new “obsolete” P-40C. > [@Boyo\_Jim](#): > > I’m very doubtful it would have happened. More likely the Americans would have swaggered out expecting to stomp on the Japanese and instead got their own ass whipped. Why? > [@Boyo\_Jim](#): > > 1. Referring to my post above, there were almost no aircraft available capable of mounting an effective attack against the Japanese fleet, and no pilots at all with combat experience. A battle between the two fleets would be a surface fleet attacking a fleet with 6 carriers. > > 2. Even had the US been able two get two carriers to Pearl Harbor on time, they would have been outnumbered 3-1. And again, the Americans had inferior planes and their pilots had zero combat experience, against Japanes pilots who had something like four times the flight time and substantial combat experience in China. The Lexington carried 78 planes, and the Enterprise has 90. You’ve got 139 land based fighters plus some more older planes. So, there are over 300 planes. Against the the Japanese had 387 planes plus broken down spares. When you look at the types of planes the Japanese had, there were 108 Zeros. The odds aren’t that bad against the US. Any Japanese advantage is more than made up by the surprise by the Americans. You are the commander in the field, and you know that the Japanese are approaching. Why is it that you are going to allow the planes to take off? Even if you stupidly sat around and waited until the first wave (189 planes) takes off (for which someone is going to get court marshaled) they don’t know where your carriers are (unless you are going to tell them. . . ) but you know where there’s are. I just simply do not see it. You know they are coming. They don’t know you know. You’ve got land-based fighters. You’ve got carrier based planes. You’ve got 8 battleships, 8 cruisers, 30 destroyers and 4 submarines. And you’re going to get your ass whipped? If so, they shouldn’t wait for the court marshal. Shoot you on the spot. The Japanese navy is headed to the bottom the the Pacific. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [September 18, 2012, 1:34pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/45 "2012-09-18T13:34:03Z")
> [@Boyo\_Jim](#): > > Actually, no, assuming _cckerberos_ is correct that the Japanese made the final “go” decision on December 2, then I was giving the American fleet the maximum available time – the same amount of time as the Japanese fleet had before the attack was launched. Bullshit. Sorry. That’s pretty strong, but the Japanese had started planning for the attack back in the summer of '41. They developed special modifications for torpedo bombs to allow them to be used in Pearl Harbor’s shallow waters, for example. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [September 18, 2012, 1:48pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/46 "2012-09-18T13:48:18Z")
> [@TokyoBayer](#): > > Bullshit. Sorry. That’s pretty strong, but the Japanese had started planning for the attack back in the summer of '41. They developed special modifications for torpedo bombs to allow them to be used in Pearl Harbor’s shallow waters, for example. I didn’t ask when they started planning a possible attack. I asked when they decided _to_ attack. It is implausible in the extreme to believe that the US would have received warning of a Japanese decision to attack before the Japanese took the decision to attack. It is equally implausible to believe that the US would strip they Atlantic fleet, which was already engaged in (admittedly low-level) combat with German submarines, in order to reinforce against an attack that they weren’t yet sure was going to happen. They were already in that situation in REAL timeline of events – they thought an attack was likely – and we all know how much they prepared based on that knowledge. :rolleyes: The Americans fighters were obsolete rolling out of the factory. The Japanese slaughtered them throughout the first year of the war. The only fighter that could even come close to holding its own was the Wildcat. But, as I already said, I have hijacked this enough, so I’m not going to respond anymore. If you think this is an interesting enough discussion for its own thread, I invite you to start one. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [September 18, 2012, 2:47pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/47 "2012-09-18T14:47:02Z")
> [@Boyo\_Jim](#): > > I didn’t ask when they started planning a possible attack. I asked when they decided _to_ attack. It is implausible in the extreme to believe that the US would have received warning of a Japanese decision to attack before the Japanese took the decision to attack. It is equally implausible to believe that the US would strip they Atlantic fleet, which was already engaged in (admittedly low-level) combat with German submarines, in order to reinforce against an attack that they weren’t yet sure was going to happen. They were already in that situation in REAL timeline of events – they thought an attack was likely – and we all know how much they prepared based on that knowledge. :rolleyes: Even the barest understanding of the Pacific theater would demonstrate the complete fallacy of this reasoning. Quoting from length from wiki, which is short but summaries it well: > [@](#): > > Preliminary planning for an attack on Pearl Harbor to protect the move into the “Southern Resource Area” (the Japanese term for the Dutch East Indies and Southeast Asia generally) had begun very early in 1941 under the auspices of Admiral Isoroku Yamamoto, then commanding Japan’s Combined Fleet.[25] He won assent to formal planning and training for an attack from the Imperial Japanese Navy General Staff only after much contention with Naval Headquarters, including a threat to resign his command.[26] Full-scale planning was underway by early spring 1941, primarily by Captain Minoru Genda.[citation needed] Japanese planning staff studied the 1940 British air attack on the Italian fleet at Taranto intensively. It was of great use to them when planning their attack on U.S. naval forces in Pearl Harbor.[nb 7][nb 8] > > Over the next several months, pilots trained, equipment was adapted, and intelligence collected. Despite these preparations, the attack plan was not approved by Emperor Hirohito until November 5, after the third of four Imperial Conferences called to consider the matter.[29] Final authorization was not given by the emperor until December 1, after a majority of Japanese leaders advised him the “Hull Note” would “destroy the fruits of the China incident, endanger Manchukuo and undermine Japanese control of Korea.”[30] > > By late 1941, many observers believed that hostilities between the U.S. and Japan were imminent. A Gallup poll just before the attack on Pearl Harbor found that 52% of Americans expected war with Japan, 27% did not expect war, and 21% had no opinion.[31] While U.S. Pacific bases and facilities had been placed on alert on multiple occasions, U.S. officials doubted Pearl Harbor would be the first target. They expected the Philippines to be attacked first. This presumption was due to the threat that the air bases throughout the country and the naval base at Manila posed to sea lanes, as well as the shipment of supplies to Japan from territory to the south.[32] They also incorrectly believed that Japan was not capable of mounting more than one major naval operation at a time.[33] The final rubber stamp occurred in December but as every indication the decisions of Hirohito on the war counsel were formalities, it’s much closer to the analogy that the final decision on which date to launch D-day wasn’t until the last moment. Surely one cannot for a moment believe that the Japanese pulled the entire plan on how to attack Pearl Harbor in five days? Seriously? WFT?:rolleyes: The information wasn’t leaked to the West, obviously. However, the battle plans existed months and months before the attack, and there is absolutely no logical basis for the arbitrary statement that it took a rubber stamped decision to allow them to be gotten. Without that wrong assumption, the rest of the argument fails. Yes, the US would gladly transfer several carriers worth of fighters over to Hawaii to knock out the IJN. As is given in the quote above, the issue was not that Japan would or would not go to war, but the US didn’t expect them to hit Pearl Harbor and not with that degree of sophistication. Since the OP is talking about the US destroying the IJN fleet, one would assume the US had credible information. I cannot see how it can be argued that would only occur after Dec 2. > [@](#): > > But, as I already said, I have hijacked this enough, so I’m not going to respond anymore. I’ve said my piece. It is a hijack so we can return to the regularly schedules program. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [September 18, 2012, 6:59pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/48 "2012-09-18T18:59:59Z")
> [@Boyo\_Jim](#): > > These are the reasons for my opinion that more warning would actually have been worse. > > 1. Referring to my post above, there were almost no aircraft available capable of mounting an effective attack against the Japanese fleet, and no pilots at all with combat experience. A battle between the two fleets would be a surface fleet attacking a fleet with 6 carriers. What about the planes at the land bases? [QUOTE=Wikipedia] The first mass flight of bombers (21 B-17Ds) from Hamilton Field, California arrived at Hickam on 14 May 1941. By December, the “Hawaiian Air Force” had been an integrated command for slightly more than one year and consisted of 754 officers and 6,706 enlisted men, with 233 aircraft assigned at its three primary bases: Hickam, Wheeler Field (now Wheeler Army Airfield), and Bellows Field (now Bellows Air Force Station). [/QUOTE] ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 18, 2012, 7:17pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/49 "2012-09-18T19:17:04Z")
Probably already been answer, but I’ll take a shot at some historical speculation: > [@](#): > > Imagine that America knew all about the impending attack on Pearl Harbour. The Japanese fleet walks into a trap, and is almost totally destroyed (a sub or two escape). America makes use of this and does NOT declare war. What does Japan do, and how does this affect the European theatre? Well, I can’t see the US not declaring war, for a starter. I mean, obviously if we got word of the exact time and place the attack was going to happen, and we chose not to try and openly or behind the scenes let the Japanese know we knew to prevent the attack, and instead chose to ambush the Japanese fleet AND pretty much wipe it out (assuming that was possible even with surprise), I’d say that war was inevitable. It would be a very short war, IMHO, because wiping out the cream of the Japanese fleet would have instantly halted their expansion into the South Pacific and thrown them immediately on the defensive. At a guess, the US would have moved to start interdicting the home islands and openly raiding their commerce and logistics. I doubt we’d have bothered with island hoping since it would be easier to steam the fleet to one of our forward bases (I assume we’d have kept most of our Pacific possessions like the PI if the Japanese attack had been destroyed as posited in the OP) and force a resolution at gun point. I’m fairly sure that, with their best and most competent fleet wiped out and the home islands under blockade and interdiction the Japanese government would have been more receptive to suing for peace. I’m not sure how this would effect the ongoing war in China, but at a guess we could probably have forced the Japanese to withdraw by the simple expedient of cutting off their resupply logistics from Japan to the forces in China and starving them of support. I can’t see any way the Japanese could have recovered from such an initial loss, since while they did have other capital ships, most of their best crews, especially air crews, were in the fleet that attacked Pearl. Not only would that have been a critical morale shot to the Japanese it would have been very difficult for them to recover from wrt ships and crews as well. And if it was a modern US carrier somehow transported back in time that did the deed, it would be even harder for them to take… 😛 ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [September 18, 2012, 7:52pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/50 "2012-09-18T19:52:55Z")
> [@XT](#): > > Well, I can’t see the US not declaring war, for a starter. > > 😛 I was thinking of the then-current spirit of isolation. ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 18, 2012, 9:30pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/51 "2012-09-18T21:30:49Z")
I don’t think that our isolationism would survive Japan planning a sneak attack on our fleet, even if we managed to get the jump on them. By '41 the worm had really turned on isolationism in any case, and I think the public was coming more and more to accept that war was going to happen, even for us. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [September 19, 2012, 4:21am UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/52 "2012-09-19T04:21:39Z")
> [@XT](#): > > Well, I can’t see the US not declaring war, for a starter. I mean, obviously if we got word of the exact time and place the attack was going to happen, and we chose not to try and openly or behind the scenes let the Japanese know we knew to prevent the attack, and instead chose to ambush the Japanese fleet AND pretty much wipe it out (assuming that was possible even with surprise), I’d say that war was inevitable. The US was actively preparing for a war. There is simply no way that they would not take this chance to cripple the IJN. Earlier in the thread there was a question what would the world feel if the US was justified on attacking Japan. Hello folks. The world was at war. Japan was in a bitter war in China. Would the US pass on a chance to cripple the Soviet Union at minimal cost to themselves in the early 60s? > [@](#): > > At a guess, the US would have moved to start interdicting the home islands and openly raiding their commerce and logistics. I doubt we’d have bothered with island hoping since it would be easier to steam the fleet to one of our forward bases (I assume we’d have kept most of our Pacific possessions like the PI if the Japanese attack had been destroyed as posited in the OP) and force a resolution at gun point. The US couldn’t do any island hopping, there were no islands to hop. The Japan would have not successfully invaded any strategic islands, or if they had one or two, the US could isolate them, attack their forces which had not had a chance to dig in. > [@](#): > > I’m fairly sure that, with their best and most competent fleet wiped out and the home islands under blockade and interdiction the Japanese government would have been more receptive to suing for peace. This is where I’ll disagree with you completely. Parts of the government would agree, but the power brokers wouldn’t. Japan in the prewar to war period was nuts, the army generals were especially nuts and the boys in China were certified insane as in the regime in Iran is only neurotic compared to these guys. Unfortunately for their country, they hadn’t learned the right lessons from the asswhopping they gave Russia’s B Team and their adventures on the continent against a corrupt regime fighting a civil a war. Religious fanatics have nothing on these guys. They believed they were destined to become a great country, and were prepared to sacrifice everything to prove it. Less than 70 out of feudal times, there wasn’t anything to check the army’s power. Eventually, it took burning down and bombing most of the country to get cooler heads to prevail. I doubt that anything short of that would have gotten them to change their minds. > [@Quartz](#): > > I was thinking of the then-current spirit of isolation. Which was directed much stronger toward Europe than Japan which directly threatened US interests in the Pacific. The US knew how hard it would be to fight the Germans, but had seriously underestimated Japan. Once war broke out, it would be generally supported. ---
**Author:** ![Deeg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/deeg/32/2955_2.png) [@Deeg](https://boards.straightdope.com/u/Deeg)\ **Post date:** [September 19, 2012, 6:17pm UTC](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802/53 "2012-09-19T18:17:53Z")
> [@TokyoBayer](#): > > Would the US pass on a chance to cripple the Soviet Union at minimal cost to themselves in the early 60s? If it meant openly declaring war, then absolutely it would have been avoided. [Previous page](https://boards.straightdope.com/t/what-if-the-japanese-fleet-had-been-destroyed-on-dec-6th-1941/634802.md?page=2)