OT question about Japan invading Hawaii

[ilovestrategy]

ORIGINAL: btbw

How look Jap war plan if PH gone



Where:
Red lines - area which autofall after PH lost. No any major base and no real forces for fight against. No way for reinforce or build new.
Pink area - zone which fall historically with a few changes (see below).
Green area - most fear can happen during Pacific War - Aussie cutted from USA help and can surrend or isolated. No help to European, Pacific, Burma etc. That mean easy mode for capture everyting before brown line (see below).
Brown border - zone which imagine new and only one perimeter of defense since all other directions closed via long range from any major base and lack of support.
P.S. Now if you add directions of historical assault strikes then you understand HOW HELP to Japan conquering main base of Pacific Fleet.

Japan did not have the resources to do all of that while trying to support an occupation of Hawaii. Japan would have to do more than take Hawaii. They would have to hold it and they knew the capabilities of the United States. Even without invading Hawaii the Japanese Army said no to invading Australia.

[btbw]

ORIGINAL: ilovestrategy
Japan did not have the resources to do all of that while trying to support an occupation of Hawaii.

You think Japan cannot spent a month for secure PH then conquer Brown circle? What knowledge you based on? Historical advance? It not worked cuz no try - no prize.

Japan would have to do more than take Hawaii. They would have to hold it and they knew the capabilities of the United States.

What can do USA after PH lost?
Battleships? Sunk or busy in Europe. Even if moving need a time for reach what? No base for take care about them in closest 4000km. Any damage fatal, ammo only for one battle and probably against Netties and KB. Japs have BBs too.
Carriers? Probably sunk when defend PH from nvasion or take long trip to closest major base (again 4000km) for current repair, rearm, refill and way back again to nothing under enemy strikes.
How much carriers had USA till 1943?
USA had almost zero capabalities for retake PH or blokade that area. And that happen even in much better conditions for Allies during all 1942.
1943 - it year when USA outrun Japan and start dominate anyway. But Japan poisoned by RJW and partially by WW1-Sino wars build strategy on fast advance to area which become as trade thing.

[TulliusDetritus]

ORIGINAL: btbw

ORIGINAL: TulliusDetritus

Sure, see map [8D]

Nice. Now explain why Allies dont use that wonderful way for reinforce forces in vital areas but start fight for Solomons/Guinea and numerous atolls?
Just wipe DEI oil/resources via your route and Japan surrend...

Er, the pre-war plan perhaps? [8D]

And you may well be aware that the Japanese quickly assaulted their vital objective. So in fact it was too late to reinforce this theater.

The question is IF Hawaii is out of the equation (and therefore the Pacific Ocean is a Japanese lake) you will have to do something else (if we assume a positive strategy will be chosen).

The Japanese still need the oil... You have bought time to reinforce this weak spot (the price is Hawaii, economically speaking: zero value for Japan)... [:D]

edit: anyway, I don't know why you're asking, as you apparently have all the answers. You asked what routes would they use. Well, the two first US divisions deployed in the Pacific followed that route really early (the Americal and 41st IIRC). I mean the sea lanes have been there during the last 4 centuries... You don't need to be an admiral to know all that.

[ilovestrategy]

I am basing my knowledge on "The Fall of the Japanese Empire" by John Toland and "Shattered Sword" by Parshall. Both books stated that the IJN said no to invading Australia because they did not have the manpower. And this was without an invasion of Hawaii.

According to "Shattered Sword", Hawaii had 65,000 troops on Hawaii with tens of thousands of sailors by April with I think 116,000 troops by the summer of 42. I may be wrong on the 116,000 troops. I'm going by memory.

Japan could never hope to hold Hawaii. It just did not have the support fleet to supply it. It would have been a White Elephant.

[TulliusDetritus]

ORIGINAL: ilovestrategy

I am basing my knowledge on "The Fall of the Japanese Empire" by John Toland and "Shattered Sword" by Parshall. Both books stated that the IJN said no to invading Australia because they did not have the manpower. And this was without an invasion of Hawaii.

According to "Shattered Sword", Hawaii had 65,000 troops on Hawaii with tens of thousands of sailors by April with I think 116,000 troops by the summer of 42. I may be wrong on the 116,000 troops. I'm going by memory.

Japan could never hope to hold Hawaii. It just did not have the support fleet to supply it. It would have been a White Elephant.

I am not following you here. If they capture the island I can't see a big threat coming from the sea [8D]

The US Navy must necessarily be sent to the West Coast. An invasion fleet needs air cover, local superiority. And this air power can only be provided by few and precious CVs. A really risky operation that might end in a big catastrophe.

Are you sure the cargo ships could not regularly transport rice, ammo, clothes to Hawaii to feed let's say 50.000 Japanese? I am ignoring the local population (we all know the Japanese "doctrine" [8|]).

[btbw]

ORIGINAL: TulliusDetritus
The Japanese still need the oil... You have bought time to reinforce this weak spot (the price is Hawaii, economically speaking: zero value for Japan)...

Oil dont have legs.
Sorry but reinforce by WHO?
Economy is only one part of war. Dominate in piece of ocean length 9000km is good strategy.

I don't know why you're asking

Directions on map targetted Noumea, Suva, Aussie, Guinea, Solomons etc. After that you will see 4 times more defense perimeter what must defend japanese troops. And they lost oil fields in 1945 so Allies did wrong?

[btbw]

ORIGINAL: TulliusDetritus
The US Navy must necessarily be sent to the West Coast.

With danger to GB and cancelation North Africa operation (which mean danger of lost Mediterrain theater and oil here - great gift for Panzerwaffe/Luftwaffe/Nazis werke).
And what can do fleet operated from base on West Coast if one leg is 4000km? Come for one day with danger lost fuel or sunk from small hole?

An invasion fleet needs air cover, local superiority. And this air power can only be provided by few and precious CVs. A really risky operation that might end in a big catastrophe.

KB bring that superiority. With a few more days airstrikes to airfields USA will have no planes which can bring danger even to merchant.
And big catastrophe happen. In Midway battle. Still happen. Without valuable prize even.

Are you sure the cargo ships could not regularly transport rice, ammo, clothes to Hawaii to feed let's say 50.000 Japanese?

USA can transport it. Japan can transport it too and much easier cuz logistic of japanese troops contain MUCH lesser neccessary things.

[TulliusDetritus]

ORIGINAL: btbw
Oil dont have legs.

And the enemy might destroy you if you don't pay attention to a basic principle called "time" [and space] [;)] This in war is called "adventurism". Looks like after all the Japanese understood they had to quickly seize their vital objective and ignore an "easy" prey (Hawaii)...

And they lost oil fields in 1945 so Allies did wrong?

The allies had a plan. It worked, even without grabbing the oil fields so fair enough. A workaround was found though. Put the submarines to good use and sink the tankers...

And economy is everything with a poor island like Japan. They are not the USSR. No oil = no modern war. Basically what Hitler pretended to do during the summer 1942 in the Eastern Front. But of course that lead the 6th Army to er... Stalingrad [:D]

What amazes me is that you 100% think the allies would not do antyhing to prevent this (using the precious "time"), when the Japanese are wasting their time grabbing the Mauna Loa...

As I have said above, if you don't pay attention the enemy might destroy you. After all it's what he is supposed to do.

[warspite1]

ORIGINAL: warspite1

ORIGINAL: btbw

Dont know what happen to brave Allied forces in HK/Sing/PI? But that bases lost very fast despite on "problems with logistic" by allied opinion.
Brave theoreticals moving easy divisions from USA (and other places) despite on war doctrine which mean Europe before Pacific.
Also can you show me route for reinforce oil fields by brave allied forces if PH fall?
I clearly understand what happen after PH attack and especially if it gone - panic (as it was in real) and gathering force in SF/SD/LA area. And fight with any shadow like happen incidents (when Japs was busy in China/Burma and dont cross even Wake meridian).
I know causes when brave Allied forces was about to surrend (or even surrend) to much more lesser troops despite on fact they had everything when enemy had bayonets.
It why blitz so devastating - one side ready, another dont know where and when war happen and what to do.
Divisions in PH was fully unprepared during a year after PH raid and morale was very low.
Difference in morale shown in Guadalcanal campaign when 1000 japs can disorganise and fall back to airstrip 16000 marines so they wait 3 more divisions and a few months for start attack enemy which withdraw from island.
PH happen 2 years before Allies start assault operations and 1 year before brave USN can hold position during night too.

warspite1

Why the "brave" before mentioning Allied troops - are you being sarcastic?

Apologies if I have read this wrong, but if I have you right on your reference to Guadalcanal and the point you are trying to make - I think you need to read about the campaign some more. Are you saying 1,000 Japanese held off 16,000 marines - the latter then waited a few months before beginning an attack? And then the Japanese just withdrew from the island? - like I said, if so, please read a book on the subject because what you just said is erm...complete nonsense.

warspite1

Any reason you have ignored this post - apart from the obvious?

[Gridley380]

IIRC, the Japanese succeeded in exactly ONE assault beach landing in the entire war - at Wake. Everywhere else they landed on a nominally hostile but tactically undefended shore, or failed.

And the first assault on Wake was thrown back.

Oahu is going to be Wake x10 - the FIRST attack. Shattered Sword, as noted above, makes a good case that the Japanese would have been thrown back had their amphib force reached Midway, based mostly on the actual Japanese record of opposed assault water crossings and other factors.

If three divisions magically show up off the beaches of Oahu on the 8th (transports aren't going to be able to close on the 7th during daylight without being spotted), they're going to face proportionally heavier CD fire than at Wake, a higher ratio of defenders, and a defense in depth. The second Wake assault only barely succeeded - the communication and supply failings that led to the US surrender won't be present at Pearl (Wake was an outpost short on everything - Pearl was a major base and well provisioned on rations and water along with things like small arms ammo).

All that ignores how the Japanese hide three divisions moving across the Pacific, or find the ships to move them in, or the escorts for them, or the oilers to top off the escorts...

As for a blockade... based out of where? Ship's magazines only carry so much, then you need to sail back to a base (Truk, realistically) to rearm. UnRep of ammo simply isn't going to happen in 1941.

The US had four infantry regiments in fighting shape on Oahu, plus most of the combat support for two triangular divisions and a huge array of coastal defense artillery (up to and including 16" guns). The US historically erected barb wire obstacles and dug trenches to defend the beaches on the 7th even though no invasion force had been spotted. On the 8th the Japanese are going to meet troops in hasty entrenchments covered by powerful CD batteries who have gotten over their shock and switched to anger.

1st Wake assault writ large.

[Canoerebel]

How in the world could Japan have invaded and held the Hawaiian Islands if they barely managed to get a division ashore at Guadalcanal over an extended period - and never managed to get the division's heavy gear ashore?  Guadalcanal and Pearl might not be completely similar since Japan might have been able to get more ashore at Guad had they managed to control the air, but the operation as a whole illustrated just how poor Japan was for managing a major amphibious operation.

Hawaii?  No way.

[Bullwinkle58]

ORIGINAL: Canoerebel

How in the world could Japan have invaded and held the Hawaiian Islands if they barely managed to get a division ashore at Guadalcanal over an extended period - and never managed to get the division's heavy gear ashore?  Guadalcanal and Pearl might not be completely similar since Japan might have been able to get more ashore at Guad had they managed to control the air, but the operation as a whole illustrated just how poor Japan was for managing a major amphibious operation.

Hawaii?  No way.

Anyone who has visited Oahu would scoff at two divisions being able to do anything except secure the core harbor and naval base. Nothing else.

Oahu is a big island, even in 1941 it was densely populated compared to places like Saipan, and the civilians were fiercly loyal Americans. It has mountains where it is easy to hide, and a lot of civilian weapons. Military personnel taking off their uniforms look exactly like farm workers until they cut your throat. There are lots of beaches where small quantities of military supplies could have been landed from the WC at night. Occupation troops would have bled.

[btbw]

ORIGINAL: Canoerebel

How in the world could Japan have invaded and held the Hawaiian Islands if they barely managed to get a division ashore at Guadalcanal over an extended period - and never managed to get the division's heavy gear ashore?  Guadalcanal and Pearl might not be completely similar since Japan might have been able to get more ashore at Guad had they managed to control the air, but the operation as a whole illustrated just how poor Japan was for managing a major amphibious operation.

Hawaii?  No way.

If Japan intel reported about battalion of US troops in Guadalcanal and genius Yamamoto save his battleships in Truk (Hasiro Fleet how it called) then yes - no way to bring ID to Guadalcanal (no reason and no ability).
Question is why brave Marines spent 3 ID and a few month against so weak enemy?

Oahu is a big island, even in 1941 it was densely populated compared to places like Saipan, and the civilians were fiercly loyal Americans. It has mountains where it is easy to hide, and a lot of civilian weapons. Military personnel taking off their uniforms look exactly like farm workers until they cut your throat. There are lots of beaches where small quantities of military supplies could have been landed from the WC at night. Occupation troops would have bled.

Civilians aganst japanese soldier? Dont make me laugh.
Oahu and loyal? Seriously? What about FIVE internment camps. Or natives, do you remember how PH become as american and what status it have?

[mike scholl 1]

ORIGINAL: btbw

ORIGINAL: Canoerebel

How in the world could Japan have invaded and held the Hawaiian Islands if they barely managed to get a division ashore at Guadalcanal over an extended period - and never managed to get the division's heavy gear ashore?  Guadalcanal and Pearl might not be completely similar since Japan might have been able to get more ashore at Guad had they managed to control the air, but the operation as a whole illustrated just how poor Japan was for managing a major amphibious operation.

Hawaii?  No way.

If Japan intel reported about battalion of US troops in Guadalcanal and genius Yamamoto save his battleships in Truk (Hasiro Fleet how it called) then yes - no way to bring ID to Guadalcanal (no reason and no ability).
Question is why brave Marines spent 3 ID and a few month against so weak enemy?

Have you ever read a book about the Pacific War? The Japanese brought (or tried to bring) two plus Divisions to Guadalcanal, which is what dragged out the operation for 6 months. As I said earlier, the only chance the Japanese ever had to get ashore successfully in Oahu was if they had done it by 8 December of 1941. And the act of trying to bring a large troop convoy halfway across the Pacific to do so would have almost guaranteed the loss of suprise at PH and doomed the invasion anyway.

[btbw]

ORIGINAL: mike scholl 1
Have you ever read a book about the Pacific War? The Japanese brought (or tried to bring) two plus Divisions to Guadalcanal, which is what dragged out the operation for 6 months. As I said earlier, the only chance the Japanese ever had to get ashore successfully in Oahu was if they had done it by 8 December of 1941. And the act of trying to bring a large troop convoy halfway across the Pacific to do so would have almost guaranteed the loss of suprise at PH and doomed the invasion anyway.

If you miss japanese imagine of situation then you read wrong books. Intel about enemy force determine counterattack size. And if 17 army think they can kill with Ichiki Det. landed 2000 americans - it problem of Intel but not convoys.
When Japan redirect REAL force to Guadalcanal it was too late - operating HF and lack of own airfields in range of figthers/DBs make convoy trip to here deadly.
So you think 1st Marine Division was losers which cannot be compared with resting troops in Pacific paradise?
About detection of convoys - again found map with trade routes (naval recon around Hawaii dont started till war, air recon was sporadic). Merchants dont have surveliance equipment for find and track enemy ships when japanese escort can. Even one float patrol plane extend vision of convoy a few times more. DO you know what happen when Brits seen invading fleet? NOTHING. War dont started yet.

[Bullwinkle58]

ORIGINAL: btbw

Civilians aganst japanese soldier? Dont make me laugh.

Read what I wrote.

Oahu and loyal? Seriously?

Yeah. I've lived there twice. The second time I worked with people who were kids and teens there during the war. What have you got?

What about FIVE internment camps.

Which opened in mid-1943, long after Japan could have inivaded. They held a few hundred prisoners, mostly Germans, Italians, and Korean workers captured during the Gilberts campaign. Hardly the internment camp effort of the mainland. Which BTW produced the most decorated US Army unit of the war.

Or natives, do you remember how PH become as american and what status it have?

Like I said, I lived there. During the war the residents of Hawaii considered themselves American.

[btbw]

ORIGINAL: Bullwinkle58

ORIGINAL: btbw

Civilians aganst japanese soldier? Dont make me laugh.

Read what I wrote.

Oahu and loyal? Seriously?

Yeah. I've lived there twice. The second time I worked with people who were kids and teens there during the war. What have you got?

What about FIVE internment camps.

Which opened in mid-1943, long after Japan could have inivaded. They held a few hundred prisoners, mostly Germans, Italians, and Korean workers captured during the Gilberts campaign. Hardly the internment camp effort of the mainland. Which BTW produced the most decorated US Army unit of the war.

Or natives, do you remember how PH become as american and what status it have?

Like I said, I lived there. During the war the residents of Hawaii considered themselves American.

Please talk about 170000 (1/3 of population) japanese on Hawaii imprisoned at 5 camps after war started.
Even mainland interned 10000 lesser japs. Who this civilians join if Japan invade?
Italians and german? Korean? It ridiculous. Most interned people was japs.
And how annexed territory can be LOYAL? What about season workes poor like hell? They support USA too? So USA limited their ability for move from islands? Great patriotic population!
Im understand your feelings but WW2 it not modern time and have alot questions which look now as impossible.

[mike scholl 1]

ORIGINAL: btbw

ORIGINAL: mike scholl 1
Have you ever read a book about the Pacific War? The Japanese brought (or tried to bring) two plus Divisions to Guadalcanal, which is what dragged out the operation for 6 months. As I said earlier, the only chance the Japanese ever had to get ashore successfully in Oahu was if they had done it by 8 December of 1941. And the act of trying to bring a large troop convoy halfway across the Pacific to do so would have almost guaranteed the loss of suprise at PH and doomed the invasion anyway.

If you miss japanese imagine of situation then you read wrong books. Intel about enemy force determine counterattack size. And if 17 army think they can kill with Ichiki Det. landed 2000 americans - it problem of Intel but not convoys.
When Japan redirect REAL force to Guadalcanal it was too late - operating HF and lack of own airfields in range of figthers/DBs make convoy trip to here deadly.
So you think 1st Marine Division was losers which cannot be compared with resting troops in Pacific paradise?
About detection of convoys - again found map with trade routes (naval recon around Hawaii dont started till war, air recon was sporadic). Merchants dont have surveliance equipment for find and track enemy ships when japanese escort can. Even one float patrol plane extend vision of convoy a few times more. DO you know what happen when Brits seen invading fleet? NOTHING. War dont started yet.

Yes, I do know what happened when the Brits tracked the Singora landing force for a week before the war. They couldn't determine if it was going to Thailand or Malaya, and they weren't going to start a war over Thailand. But a massive Japanese troop convoy in the Central Pacific? No way that can be anything but what it is..., an act of war! So much for suprise at PH. I will agree with you that Japanese intelligence SUCKED. But as to the 1st Marines, they kicked the snot out of everything the Japanese through at them. The "brave" Japanese troops were brave enough, but their leaders were morons who threw them away in pennypackets.

[panzer cat]

Even if Japan could have lifted 2 or 3 divs across the VAST Pacific ocean, she did not have the landing craft(and probably not the doctrine, see Guadalcanal) to get this force ashore, supplied, resupplied. It has also been pointed out that the Pacific ocean can be very rough in december. Lets not forget the subs interdicting Hawaii, lots of islands to place subtenders. And you better take Pearl quickly, otherwise it's a long way to Truk to resupply your warships.

[btbw]

ORIGINAL: mike scholl 1

Yes, I do know what happened when the Brits tracked the Singora landing force for a week before the war. They couldn't determine if it was going to Thailand or Malaya, and they weren't going to start a war over Thailand. But a massive Japanese troop convoy in the Central Pacific? No way that can be anything but what it is..., an act of war! So much for suprise at PH. I will agree with you that Japanese intelligence SUCKED. But as to the 1st Marines, they kicked the snot out of everything the Japanese through at them. The "brave" Japanese troops were brave enough, but their leaders were morons who threw them away in pennypackets.

Brave Marine was so quick and agressive so wait another 2 IDs and then start advance till japs dont evacuate.
Please divide emotions and patriotic from facts. In 1941-1942 US troops on Pacific was unadequately weak and untrained. Only continous training and experience from previous battles make them strong like in 1944+.
ACT OF WAR in 1941 dont have any signs of detected fleet since USA dont have ANY DETECTION SYSTEM. Pacific Ocean different from limited seas like Siam Gulf. And found here (by who?) even a fleet was almost impossible without SPECIAL forces detached to do that and in big numbers.
USA patrolling waters around Hawaii but less then 1-day trip for troop convoy and by very limited planes in limited arcs. All that was very known by jap intel since they study it (zillion time better then Guadalcanal).
IMHO Japan count they dont need PH and it why they dont try invade here but if they prepare invasion like KB strike then it have a chance ot success. Typical "What if".