"Hypothetical Pearl Harbor" Topic

Hello all

Just wanting some thoughts and suggestions. Me an a friend are thinking of doing a hypothetical mini campaign or large game.

Idea is what if the US fleet was warned ahead of time, and they got up to speed and out of the harbor and meet the IJN fleet at sea.

Second idea the Americans get planes up and have a large CY6 air game against the first wave, then what makes it gets thru to Pearl. then use the seekreig 5 rules to do the attack runs on the ships at port.

Looking for thoughts on percent chances of the fleet getting out to sea. and any other thoughts about possible ideas.

fullmetal

It would have taken a little bit more warning than the Pacific Fleet got – on Sunday morning Dec 7th a lot of the officers and crew were on shore leave; I think on some of the smaller ships the highest ranking officer on board was an ensign

Still, if the US had a day or two of warning they could have assembled a fairly impressive battle line

Remember that until the attack there was no reason to harm the IJN

Interesting what ifs come in to play.

Historically, the US military was operating under peacetime practices. Ammo and arms were locked up for the weekend. Ships were rotated in and out of port with those in port on liberty. Large quantities of planes and other equipment were offline for maintenance.

On a wartime footing, a lot of that would have been different. Earlier response and larger effort. However, a lot of equipment was older vintage and was in line for replacement or upgrade. It would be interesting to see how some of these older weapon systems would have held up.

The Japanese too were working with green crews and pilots due to the recent fleet expansion. Some of this showed up in the actual attack.

Your options above would have to be prepared and out to sea or fight from within the harbor. It took a long time to go from power being supplied almost exclusively from on shore to getting moving under your own power. When the Nevada tried to make a run, the Japanese pilots worked really hard to sink her in the channel to block it.

To me it would seem odd that the Army and Naval aircraft would be ready to defend and counterattack but the ships would still be in port doing basically nothing ahead of time.

Your "out to sea" option seems more the likely of the two.

Thinking further an out at sea naval/air battle would be interesting. Much of the US long range recon and bomber force was destroyed on the ground.

A combined carrier and land-based strike by the US would have been interesting. The poor schmuck coordinating between the Naval and Army air forces would have won a double or triple Medal of Honor just for having to work between the two.

Would have made it a lot more difficult to recover sunken ships.

I was not aware the Japanese had green crews, but I assume they were much more prepared for war than the Americans.

Remember that until the attack there was no reason to harm the IJN

Yes there was. The presence of such a fleet near Hawaii is tantamount to war. One can certainly assume hostile intent. A fleet on a friendly tour would arrange things diplomatically. It's presence at that point can only be a hostile act.

And the Americans would have charged right into them. And would have been sunk since they were not prepared for war. We were not as good as we thought we were. After Midway, Spruance actually had to justify not taking the Japanese in a surface action. Look to Savo Island two months later to see how prepared the USN was for surface battle. It took quite a few hard lessons to be ready.

While I agree with Winston that US force commanders could assume hostile intent, I'm not sure about 'real world' intrusions into the military.

For instance, the Soviets allowed a massive build up of German armed forces literally on their border and then refused to believe that they were being attacked, or that the local Soviet forces hadn't in some way precipitated the whole thing.

So, while I don't think it is clear cut, I'm more inclined to think that FDR would have been a heck of a lot happier with at least some damage being done to the Japanese fleet rather than the historical outcome.

That said, the US fleet was still expanding itself and had a lot of inexperienced sailors and commanders.

The presence of such a fleet near Hawaii is tantamount to war.

Disagree.

The presence of such a fleet near Hawaii is not an act of war. Nor is it "tantamount" (adj: equal to in value, meaning or effect)to war.

Throughout the 19th and 20th centuries and on into today, sailing a force of warships that is disproportionately powerful for normal or legitimate purposes, near to your adversary's vital interests, has been a frequently used technique to intimidate. But it is an intimidation that is notably short of war. The terms we use to describe such behavior are "sabre rattling" and "gunboat diplomacy".

If the Japanese fleet had been discovered it would have been reasonable for the US Pacific Fleet to sortie (even on a "wartime footing"), and for the Pearl Harbor defenses to go on full alert. But it would not have been at all likely, nor at all reasonable, for the US Pacific Fleet to attack the Japanese fleet.

The result would indeed be interesting to game out. At least I would be quite interested. But I fear that the results would have been substantially worse for the USN.

I see the risks rising for both sides. Alert defenses mean bigger risks to the Japanese. But the USN would have been inclined to put to see, and I think that amplifies the US risk substantially.

Clearly conceived and communicated "rules of engagement" are, I believe, a relatively recent concept that were not included in a commander's orders in that timeframe. I would expect a flurry of furious messaging within both forces as commanders seek instructions. This in a day when instant connectivity was not only not a given, but not even a possibility.

As we know the Japanese intention was war. The US intention was not. So the Japanese have the initiative. They decide if, and when, the first battle takes place.

The USN would be second-guessing and sparring with recon assets, trying to keep track of the Japanese fleet while determining it's potential and debating it's intent. The Japanese, on the other hand, would be trying to track the US fleet while making a final determination whether to recall their fleet (due to loss of surprise), or to initiate an attack. Once that decision was made, the Japanese would be preparing a strike, while the US would still be stuck in the second-guessing mode.

The USN carrier commanders were a very aggressive bunch. But they were at a disadvantage. First and foremost, there were only 2 US carriers (Lexington and Enterprise), while there were 6 Japanese carriers. Add to this that the US carriers would have been the least prepared for combat on December 7 among all the forces on both sides. They were out of port, at the end of their missions, and had not departed Pearl on a war footing. Both were on ferry missions, with Lexington making the run to Midway, and Enterprise to Wake. Both had shipped with their full airgroups (in addition to the Marine aircraft they were ferrying), but I have not seen any information on what stores they carried. I don't expect they carried too much, either in combat stores (avgas and ammo) or in sustenance (food, water, ship fuel).

After the actual attack the two carrier task forces (both sailed with cruisers and destroyers in escort) rendezvoused south of Oahu to conduct search operations.

I expect that the if the US battle fleet sortied on December 5 or 6 (or even the morning of December 7), within hours they would have tied up with the CV task forces. I don't know how the combined force would have been organized, but my understanding is that the USN doctrine at that time envisioned CVs operating separately of each other within their small task groups, to scout around or ahead of the main battle fleet.

Within one or two days they would probably have been looking to send the CVs in to Pearl to get stocked up. Any smart fleet commander would have done this one CV at a time. So if the Japanese took longer than that time to reach their own conclusion, they might well have faced only a single CV with the US fleet when they did strike.

The US battle fleet at that time would have been very poorly equipped to fight off an attack by the 6 CVs of Kido Butai, if they launched against the fleet and found it. Japanese doctrine called for consolidated strike efforts (versus the independent approach the USN used). So we are looking at more than 200, and maybe as many as 360 aircraft attacking. Against this, even both US carriers would muster at best 32 fighters (16 Buffaloes on Lexington, 16 Wildcats on Enterprise). If only 1 of the 2 US carriers is present, or if they don't get all their fighters up in time, well … even if they do it doesn't look too good.

If the two fleets know each other's location, and the Japanese have the initiative to strike first, it just doesn't look good for the USN. At least not to me.

-Mark
(aka: Mk 1)

What were the Japanese plans in case the US fleet had sortied? Were they supposed to break off and head home or attack anyway? Most likely yes since the other attacks were already planned. A quick look at documents reveals very little about what the plan was if the US fleet had sortied.

Given Japan and the US seemed headed towards war in the Pacific then the events of Pearl Harbor were, dare I say, fortuitous. The sheer imagery combined with the words of President Roosevelt united a country split on the question of war with the majority previously preferring to stay out of it in any location.

While it is interesting, and may make for some terrific gaming scenarios, a sortie by the US fleet would have been a disaster. First remember this. Pearl Harbor is relatively shallow and, despite the British example at Taranto, believed to be safe from air dropped torpedoes. It was that same shallow configuration which saved so many ships. By various counts there were some 98 Navy ships of all types in Pearl the morning of the 7th. The final toll however was only 3 ships permanently lost! The Arizona exploded. The Oklahoma was raised but it was decided she was too old to repair. And the Utah was deemed obsolete.

Now any ship sunk or severely damaged on a sortie would be permanently gone. Further with so many sailors ashore and the fact that those aboard ships damaged were in port and could be relatively easily recovered the loss of life was minimized. Even more importantly at that point critically trained manpower saved.

And while perhaps the thought of the Japanese and US battleship lines slugging it out might be an inspiring thought the fact of those 6 carriers, which would not be standing by idle, would have ended any chance the US may have had in prevailing in such a fight. If in fact they could even close to surface engagement ranges that is.

Of interest perhaps is Matrix Games computer game Warplan Orange which covers a possible US-Japanese naval war 1922-1930, before the carriers emerge. Avalanche Press has their board game of the same name covering 1920-1936. Now there we can satisfy our desire to see them slug it out :)