Alternatives to Pearl Harbour?

[Tallil2long]

The total for the whole attack was 29 shot down and about 121 damaged. Of the damaged total, many were only superficially damaged. Assuming 70 of the total had too much damage to be certified for flight again that day and 50 could fly, Nagumo "only" will have had 300 aircraft, or still 80 more than at Midway. Assuming NONE were able to fly again that day, Nagumo will still have had 250 aircraft immediately available, still about 20 more than at Midway.

So any way you slice it, there is no explanation for no follow up attack.

How long would it take to prepare, lauch, execute and recover another strike? Given how tight the fuel situation was, could he afford to stooge around for that long?

Further, even if there were absolutely no U.S. submarines about, Nagumo couldn't know that. Every hour he spent in the area meant (as far as he knew) greatly heightened chance of sub attack. Or carrier attack. Or land-based air attack. As far from home as he was, a damaged carrier likely meant a lost carrier. And Japan could not afford to lose even one.

Arguments that it was a mistake not to launch a further strike seem to hinge on Nagumo have perfect intel, as if in a wargame.

 

[phx1138]

Before you even raise the question, you've got to get Yamamoto (& Japan) thinking it's going to be a long war, to get them to change the priorities.

That done...First strike on the tank farms & the power station. KO the power station, you cripple the Yard no matter what. Take out the fuel, the Fleet, even the subs, are done.

Second strike on the barracks--&, more importantly, on the Admin Building. Not to get Kimmel or his staff--to get Hypo, which is in the basement.

Go home a hero. Make Yamamoto look even smarter. Lose the war in 1945 anyhow...

 

[Admiral Halsey]

How long would it take to prepare, lauch, execute and recover another strike? Given how tight the fuel situation was, could he afford to stooge around for that long?

Further, even if there were absolutely no U.S. submarines about, Nagumo couldn't know that. Every hour he spent in the area meant (as far as he knew) greatly heightened chance of sub attack. Or carrier attack. Or land-based air attack. As far from home as he was, a damaged carrier likely meant a lost carrier. And Japan could not afford to lose even one.

Arguments that it was a mistake not to launch a further strike seem to hinge on Nagumo have perfect intel, as if in a wargame.

I've always thought of it as him being a bit to cautious. If Yamamoto had been there he would've taken the gamble of the 3rd strike at minimum. He may have even stayed around to try and catch the American carriers even. Still long term it doesn't matter how bad Japan destroy's Pearl as they'll lose anyways.

 

[AdA]

Last time we had a Pearl thread the matter of range was pointed out as a severe limitation to a US land based aircraft strike.

The only possible rational explanation for the IJN war plan is that they expected the Germans to defeat the USSR, and some sort of peace conference to take place mid 1942, at which time they would be holding all the good cards.

They did their part of the plan. Reality intervened, as it normally does with plans...

 

[Glenn239]

How long would it take to prepare, lauch, execute and recover another strike?

Assuming another attack on Hawaii was ordered before the first strike returned, maybe 2 hours to recover, prep and spot after 10am, 4 hours to launch, attack, return and land, so about 6 hours needed in total.

Given how tight the fuel situation was, could he afford to stooge around for that long?

The fuel situation was fine.

Further, even if there were absolutely no U.S. submarines about, Nagumo couldn't know that. Every hour he spent in the area meant (as far as he knew) greatly heightened chance of sub attack. Or carrier attack. Or land-based air attack. As far from home as he was, a damaged carrier likely meant a lost carrier. And Japan could not afford to lose even one.

If Nagumo's decision was not extremely contraversial, then obviously it would not have caused as much contraversy as it did, even in the fleet, even at the time.

None of the things you list imply Nagumo could not have attacked, and some of them (submarine attack) imply that IJN carriers should be too timid even to poke their bows out of the Inland Sea.

 

[Glenn239]

Before you even raise the question, you've got to get Yamamoto (& Japan) thinking it's going to be a long war, to get them to change the priorities.

Right, arguments that the IJN needed to preserve carriers is not IJN doctrine from 1941. The IJN of 1941 believed that it had to win a short war, and if the carriers were lost doing so, c'est la vie. Yamamoto, if following along today, would probably look on blankly as posters try to explain the IJN should husband its forces to fight a long war, the very war Yamamoto KNEW he could not possibly win.

 

[Saphroneth]

Ai yi...
Yes, there would be enough aircraft to do a lot of damage. That's not really in contention.
What is in contention is:
> With the extra prep time, and not being surprised, and in general not being in "It's Sunday and we're at peace" mode, the US defences will inflict a lot more damage than even the second wave suffered.
> The remaining good targets aren't even there, or aren't vulnerable (carriers and oil, respectively)
> The attrition taken in a third strike will materially impact the capabilities of Kido Butai, big time.
> Fuel concerns. Both AvGas and DD dwell time.
> And "more than Midway" is being thrown around. Need it be said that Midway didn't work? The strike on the island failed, and the fleet cohesion of KB basically fractured under the strain.

 

[Tallil2long]

The fuel situation was fine.

If Nagumo's decision was not extremely contraversial, then obviously it would not have caused as much contraversy as it did, even in the fleet, even at the time.

None of the things you list imply Nagumo could not have attacked, and some of them (submarine attack) imply that IJN carriers should be too timid even to poke their bows out of the Inland Sea.

Ah. Everything I've read suggested that Kido Butai was operating at the ragged edge of its range. But if you say otherwise, okay.

Controversy often arises from those who weren't in charge and didn't have to be personally responsible for taking the risk. Hindsight helps, too. The existence of controversy doesn't mean the original decision wasn't the best available balance of risk and reward.

Strawman argument. In fact, Submarines were never regarded as an on/off threat -- either you can leave port or you can't. The longer you loitered in one spot, or the more times you used the same transit route, etc, the greater the risk of sub attack. Or any other kind of attack, for that matter. So while sub attack was a risk that just had to be taken, it was one you didn't trifle with foolishly.

 

[Shadow Master]

I just would like to ask:
What was the comparitive air strength remaining in Hawaii vs that in midway?

Examples showing more KB airstrength than at midway seem to be a bit lopsided, as there were also much stronger US airforces remaining in and around PH, not to mention more air defences (whose gunners won't be cought napping), that would, IMO, far more than offset this. Then add in the US carriers possible involvement...

Any thoughts?

 

[phx1138]

Honestly, I have a suspicion Yamamoto proposed attacking Pearl half-hoping it would be rejected, because he knew damn well it was nutty. And because he suspected the Army was too clueless about the U.S. to listen to his "6mo window": namely, if you can't win in 6m, don't start something, because the U.S. is gonna finish it.

That went so well...

 

[Saphroneth]

Regarding targeting personel, if the houses in the "wisteria lane" on the lower left side of this photo are the residence of the critical personel, they are hard targets because it would require a bomb in each house to target it's resident. But if the larger rectangular buildings on the right are barracks, a 250Kg HE bomb on each one before people leave them for battle stations would do a lot more damage than hitting an hangar. It's easier to build planes than to train people.

The L shaped building on the center is probably a Command/Administrative building and would probably be manned during an attack. It's another potential target.

Incidentally, how would the Japanese know which was which and what to hit?

 

[MattII]

Another possibility for more damage would be deliberatedly targeting personel quarters in the first wave to kill as much trained personel as possible. If the strike was just before morning call, a few dive bombers putting heavy HE bombs on barracks could inflict a lot of casualties, and it would be possible to identify the critical buildings to hit (pilots quarters, aircrew barracks, etc)

Almost all of these people would be replaced even more quickly than the ships were, the real high-value targets would be things like the dry-docks, machine shops, fuel and ammunition stores, etc.

They lost a grand total of 29 planes in the two strikes. They could've easily launched a 3rd attack on the instillation's and done serious damage.

I disagree, they lost outright just nine aircraft in the first wave, but 20 in the second, and so a third wave would suffer even higher losses, especially as there's be fewer aircraft to participate, not to mention more American aircraft ready (55 aircraft escaped unscathed, at least some of them would have been fighters).

Before you even raise the question, you've got to get Yamamoto (& Japan) thinking it's going to be a long war, to get them to change the priorities.

The former is probably easier than the latter. If you can get him to accept that the battle may not bring America to the table, I can see some aircraft, rather than targeting light units, targeting infrastructure instead, things like the tank farms and the dry docks.

 

[AdA]

Incidentally, how would the Japanese know which was which and what to hit?

HUMINT, of course.

 

[AdA]

Almost all of these people would be replaced even more quickly than the ships were, the real high-value targets would be things like the dry-docks, machine shops, fuel and ammunition stores, etc.

I disagree, they lost outright just nine aircraft in the first wave, but 20 in the second, and so a third wave would suffer even higher losses, especially as there's be fewer aircraft to participate, not to mention more American aircraft ready (55 aircraft escaped unscathed, at least some of them would have been fighters).

The former is probably easier than the latter.

The BB took years to return to service, so in that sense, yes. For what was expected to be a six month war, taking out the experienced pilots, radar operators, submariners, navigators, etc, would be a hard blow.

 

[MattII]

Yamamoto wasn't expecting a six-month war, he was expecting either an immediate white flag, or a war to the finish. Also, taking out essential infrastructure is more viable than taking out people, since people can be got from the mainland, whereas infrastructure can't, at least in any reasonable time. Take the fuel farm for example, without that the Ships are limited to their range from the West Coast, not from Pearl, because before they can base from Pearl they need to rebuild the tank farm.

 

[AdA]

Yamamoto wasn't expecting a six-month war, he was expecting either an immediate white flag, or a war to the finish. Also, taking out essential infrastructure is more viable than taking out people, since people can be got from the mainland, whereas infrastructure can't, at least in any reasonable time. Take the fuel farm for example, without that the Ships are limited to their range from the West Coast, not from Pearl, because before they can base from Pearl they need to rebuild the tank farm.

In that case, what was their plan for winning, apart from having Germany win the war for them?

Regardless of what was the oficial position, Pear Harbour only makes sense within the context of an expected German victory in Europe, unless we buy into the premisse of the Japanese Empire as being fundamentaly irrational.


One on one, Japan taking on the USA in the 40s makes about as much sense as Poland invading the USSR in the 30s...

 

[Saphroneth]

HUMINT, of course.

Except that the whole reason all those aircraft were lined up was to prevent HUMINT (or, rather, saboteurs, which is to say destructive use of HUMINT) from reaching them. And - well, I suspect it's rather harder to find out which building pilots stay in at a restricted military base than it is to see where ships are moored.

 

[Derek Pullem]

What id Japan used chemical or biological weapons on Pearl Harbor in addition to the attacks on the fleet?

The US response would be even stronger than OTL but it could cripple initial US operations.

That the Japanese had these weapons is undeniable - that they would use them against non-Chinese targets is highly unlikely.

But it could deny the US the use of Pearl as a staging posts for some weeks or months depending on the agents used.

 

[AdA]

Except that the whole reason all those aircraft were lined up was to prevent HUMINT (or, rather, saboteurs, which is to say destructive use of HUMINT) from reaching them. And - well, I suspect it's rather harder to find out which building pilots stay in at a restricted military base than it is to see where ships are moored.

No it's not. On a small island people tend to know everything. Laundry gets collected, people have girlfriends and drinking buddies, civilians are invited to parties and girls eventualy make unofficial visits to pilots quarters, etc. Getting stuff like autentication codes is hard. Finding out who sleeps where in a base that has been there for years is easy...
Planes and ships get moved around. Nobody ever changes Bachelor Officer Quarters location for security reasons.

 

[Tallil2long]

In that case, what was their plan for winning, apart from having Germany win the war for them?

Regardless of what was the oficial position, Pear Harbour only makes sense within the context of an expected German victory in Europe, unless we buy into the premisse of the Japanese Empire as being fundamentaly irrational.


One on one, Japan taking on the USA in the 40s makes about as much sense as Poland invading the USSR in the 30s...

I think the Japanese outlook was just very parochial (limited and narrow in scope). They realized that they had a strong navy. That the other Powers were very, very far away. That Britain was distracted. They had only a shallow view of Total War, and really didn't understand just what depths of willpower and industrial discipline a modern Western nation was able to summon under wartime necessity. They truly thought a Really Big Blow would see the U.S. deciding that the game wasn't worth the candle.

Yamamoto knew better, but they wouldn't listen to him.

So it might seem irrational, but in fact it was rational, given a particular set of starting assumptions. The problem is that flawed assumptions result in a disastrous outcome.