Christmas Attack on Pearl Harbor

[Clandango]

This is pretty straight forward. Would it be viable to attack Pearl Harbor on December 24th or 25th? I know they attacked on a Sunday morning IOTL, though I am unsure if many having the day off or being in church was a part of the plan, or just related minorly. A lot can change when it come so to weather in two weeks, as with the fuel supplies of fleets on standby, I know. Would the two weeks make a big difference in the readiness of Dutch, British, and American forces in South-East Asia and the Pacific? Would attacking on Christmas be seen as even worse than doing it when the Japanese had diplomats in DC talking about ways to get peace in China? Also, should I have put WI in the title?

 

[Antiochus V]

This is pretty straight forward. Would it be viable to attack Pearl Harbor on December 24th or 25th? I know they attacked on a Sunday morning IOTL, though I am unsure if many having the day off or being in church was a part of the plan, or just related minorly. A lot can change when it come so to weather in two weeks, as with the fuel supplies of fleets on standby, I know. Would the two weeks make a big difference in the readiness of Dutch, British, and American forces in South-East Asia and the Pacific? Would attacking on Christmas be seen as even worse than doing it when the Japanese had diplomats in DC talking about ways to get peace in China? Also, should I have put WI in the title?

I don’t think there would be a dramatic change to British or Dutch numbers. There might be a few more troops in Singapore or Burma, but not enough to change the situation. However you can make the case that 2 more weeks of training would help the Dutch and British who had a very ‘green’ force.

It is the US and Philippines who would have seen the biggest initial impact.

-At Pearl Harbour you might have seen the radar system integrated more effectively into the system, had the US kept a squadron (or more) of fighters at a high readiness level that might have made a small difference. I don’t really know how they planned to to set up their air defence longer term though. Hard to know what ships would have been stationed there, it could have been better or worse from that point of view, though ships sunk in a harbour have a good chance of being repaired, so it might not matter long term.
-In the Philippines another big convoy could well have arrived by then, in which case the Philippine army has a lot more artillery a few more US troops and ammunition, not to mention more fighters and more radar sets. 2 weeks also allows a greater level of mobilisation and a bit more training of those already mobilised. This is probably the main danger area for Japan, potentially the Americans are able to roughly handle the first raids by the Japanese Air Force, especially if the radar is up and running and linked to the airfields properly.

I think the delay does raise the risk of the Allies building up a better picture of the proposed Japanese plans, they had been making good progress on deciphering Japanese messages, and more time means more messages read. A bit more warning for the UK means Burma might be tenable, and Force Z and other ships could be used differently.

 

[Carl Schwamberger]

Kimmel had the fleet stand down for 24 hours rest after the previous ten days of frantic activity. The largely forgotten back story to the 7 Dec attack is the War Warnings sent to Pacific commands circa 25-27 November caused a high level of alert and a lot of activity. The bulk of the fleet went to sea for a week, a maximum effort was made at air reconnaissance. Both efforts and other actions wore down the men, ran up machines on deadline, and caused some disorganization. I don't know what Shorts excuse was, but Kimmel wanted to, in modern terms, reset the fleet and return to a high alert status after a day rest. He expected very little time off for a extended period.

So, 17 days later the Navy may not have been nearly as passive as on 7 Dec. A larger portion of the fleet at sea. Submarines better deployed. The Army had control of the air defense, so I am less sure of how prepared the air wing would have been.

Had the Japanese attack Thanksgiving day, as originally planned, or the subsequent Sunday, the defense of Oahu would not have nearly as passive & the larger part of the fleet far over the horizon, probably to the south or SE. Not a well organized defense, but far more alert than 7 Dec.

 

[DougM]

I had a lot of family that was of age in 1941. With 4 Uncles in the war as well as a number of Aunts that did the “Rosie the Riviter” bit and after talking to them over the years I am willing to bet that the vast majority had no idea that diplomats where in DC. So I doubt they care one way or the other. They were pissed that it was a sneak attack. This was made worse by it being on a Sunday morning a time thatvmost in that generation viewed as a peicfull time to relax and of course we can not forget the religious connection. On top of this it was in December during the build up to Christmas so it was just made worse by being seen as happing in the “Holiday Season”.
If the Attack happens on Christmas Eve or Christmas it is just going to get the average America of the time even more pissed off. And you will see a bit harsher war. And more Japanese are going to get miss treated or justcplan killed. Not many more as not very many surrendered to begin with. But it will be harsher.
I also think it may result in a more significant war crimes trial. But I don’t think a lot will change. As for the immediate military effect of the change I doubt much changes with that. I don’t think a couple weeks is going to result in a huge change the few extra troops and the extra equipment is not going to be enough to really change much. I doubt it will result in the US discovering that attack before it happens. And no one really knows what ships will be in port and what ships won’t be. But we truly can’t say
So I think you could make an argument for anything from The US learns of the attack and thus springs a trap and destroys a large part of the Japanese attack force, to the Carriers are in port and get sunk and the Japanese are so confident because of this that they launched the “third wave “ But on the bell curve of possibilities that have those to possibilities on the ends most of the results will see very minor changes other then a lot of folks in the US are going to be even more upset.

 

[nbcman]

There would be a different moon cycle on Christmas 1941 that would provide less moonlight for overnight attacks such as the amphibious landings in Malaya as compared to 7-8 December.

 

[Carl Schwamberger]

There would be a different moon cycle on Christmas 1941 that would provide less moonlight for overnight attacks such as the amphibious landings in Malaya as compared to 7-8 December.

That just changes the hours you make the attack. I used to be paid to plan amphib ops. Selecting H hour was a shifting set of factors of which tide and illumination were a few out of many.

 

[cladglas]

[QUOTE="DougM
just off the top of my head, in usaffe, the 27th BG(L) would have their A-24s, there would be another sqdn worth of p-40s to replace p-35s, an FA bde HQ, an FA rgt HQ & 4 more 75mm battalions, possibly a radar operational near the NW tip of luzon, another b-17 sqdn, perhaps all moved to del monte, etc. the arrival of 'pensacola convoy' & the one a few days behind it would make a big difference. plus the extra time to get the kinks out of the air warning service wouldn't hurt, either. & maybe no weather delays for the japanese on 26 dec. as always, 7/8 dec 41 'what ifs' are barrels full of worms with lots of butterflies flitting around.

 

[HJ Tulp]

At the beginning of December the would-be ABDA powers were finally confirming that they would be in it together. Then Pearl Harbour happened days after. ABDA would probably not be set up in peacetime but there will be a lot of coordination done at all levels, which had to be done on the fly OTL.

 

[eltf177]

Agreed, the Pensacola convoy will get to the Philippines and not be rerouted to Darwin. Wake should get more reinforcements and they should also have revetments for the F4F's by that point. More B-17's in the Philippines (Truman's B-17's were bounced during the Pearl attack and most were destroyed). It won't help in the long run but will help in the short run...

 

[Marquis]

The RN Force Z may be in a better position, possibly leading a better integrated ABDA force.