How much diffrent would WWII if All the Axis powers had used there Subs as Ger. did

How different would WWII of been if the Axis powers had all used there Sub forces as anti merchant ships .
Think of the Japanese Sub forces doing wolf packs in the Indian ocean and the Italian navy doing the same in the Med .

When the BEFP came back in the pacific in 1944 the were worried that the IJN would have Wolf Packs against there Fleet Train .
 

Numb

Banned
well...

most likely a much mkore difficult Pacific War for the united States, much more troops lost, possibly at the most extreme the Japanese get nuked earlier as the Americans need to end the war or the USA doesnt get the nuke early enough and is forced to sign a conditonal peace tereaty with Japan, or ...

kamikaze subs?
 
"Proper" Japanese sub doctrine makes life more difficult for the USA for a while, and means either more destroyers/escorts going to the Pacific vice Atlantic or shifting some naval construction away from something else to make more. Having said that the vast distances in the Pacific and the lack of maritime recon assets in significant numbers means the Japanese have a hard time finding US convoys, which for most of the war do not have to pass through restricted waters or choke points unlike Japanese merchants on their way to Japan with raw materials. The other problem is that the Japanese simply cannot replace the subs when they lose them - making minisubs for kamikaze defense of the home islands is one thing, but once they start losing their ocean going boats they simply do not have the industrial capacity to replace them like the Germans were able to - so by late 1943 early 1944 the Japanese sub force is almost nonexistent.

Overall effect on the war - some more losses and perhaps a slight slowing of US advance, but not that much. Bigger question is how much the need to cover convoys in the Pacific takes away from Atlantic ops or building of landing craft/LSTs.
 

Anaxagoras

Banned
Correct me if I'm wrong, but weren't Japanese subs characterized by having far more range than the subs of other countries? If true, this would seem to factor into any scenario in which Japan adopted a proper submarine strategy.
 
The Italian subs were pretty bad, their large casings did not allow quick diving, but they were plentiful so if used agressiely they could achieve some success which the Allies would have to recover from. Atrittion would quickly occur for the Italians and they would lapse into impotence.

The IJN is in a similar situation, it could achieve some early success off the coast of the US, Hawaii and in forward areas such as Australia and these would have to be recovered from. But when their fleet gets atritted down the Allies will have a free hand again, probably by late 1942.
 

Anaxagoras

Banned
IIRC, one of the IJN's problems was their subs were expected to hit military vessels and ignore cargo ships.

Yes, and the OP is asking how things might have gone differently if they had adopted a policy similar to that of Germany's and used their subs to attack merchant vessels.
 

BlondieBC

Banned
Japan would hurt USA logistics, so the war would go slower because it would take longer to assemble supplies for attacks. I can't quantify, but if I had to guess, 2-3 months slower through July 1945. USA builds more escorts, so it cancel some other ship. Don't see a big impact on this one.

Italy: Don't see a big impact, Italy has to keep it subs in the Med due to Gibraltar. Nothing jumps to mind that is a game changer, but maybe we can slow down the Italian campaign by a few weeks to months.
 
How different would WWII of been if the Axis powers had all used there Sub forces as anti merchant ships .
Think of the Japanese Sub forces doing wolf packs in the Indian ocean and the Italian navy doing the same in the Med .

When the BEFP came back in the pacific in 1944 the were worried that the IJN would have Wolf Packs against there Fleet Train .

If Japan had used its subs more effectively it could have done some serious damage in the short term. However the Allied trump card in WWII is the Soviet-Japanese neutrality Pact, ensuring a major supply line for the USSR never in serious danger IOTL, thus ensuring the USSR had permanent freebie logistics and that not only would the Nazis be crushed in the USSR, but the Allies would be able to launch major crushing offensives on mainland Europe.
 
Correct me if I'm wrong, but weren't Japanese subs characterized by having far more range than the subs of other countries? If true, this would seem to factor into any scenario in which Japan adopted a proper submarine strategy.

In a sense, but the big problem for Germany is that their biggest enemy, the USSR, still gets its freebies from the USA completely unhindered, with the result that even if Japan makes life Hell for the democracies for a while the Soviets have endless amounts of Lend-Lease to draw on by 1943, ensuring the Nazis get crushed on land regardess of the war at sea.
 
Japanese have a hard time finding US convoys,
But it's an island hopping war, Japan should have a good idea where many convoys will be heading.

Depending on how hard it is to figure out what islands are next to be attacked.
 
The Japanese should concentrate their subs on the Indian Ocean, its not that far from Penang to choke points like near Aden, the Persian gulf and the big Indian ports the the ships have to go to. Japan should use her float plane cruisers too which would be effective commerce raiders.

Of course if the Allies are reading Japanese codes that will make commerce raiding ineffective anyway, the Germans at least had blackout periods where the Allies wern't reading their codes, they could offen read Allied merchant codes and even when the Allies were reading them they just had a bunch of subs so they were hard to avoid regardless.

The best thing that can happen for the Axis is lack of available shipping delays or restricts the size of Torch and/or El Alaimen and/or the buildup after, and the Allies dilly dally in Africa longer than OTL.

By mid 43 the Allies are cranking out a bunch of merchant ships and a sinking a bunch of subs so it doesn't matter much then.
 
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In a sense, but the big problem for Germany is that their biggest enemy, the USSR, still gets its freebies from the USA completely unhindered, with the result that even if Japan makes life Hell for the democracies for a while the Soviets have endless amounts of Lend-Lease to draw on by 1943, ensuring the Nazis get crushed on land regardess of the war at sea.

But most of that Soviet shipping was just reflagged U.S ships. The only hope for the Axis here here is the Allies have so many shipping problems they can't/wont reflag so many ships as Soviet for the Vladivostok lend lease route.

The July 43 OTL Atlantic U-boat defeat will pretty much end all this anyway then its business as usual for the Allies.
 
But most of that Soviet shipping was just reflagged U.S ships. The only hope for the Axis here here is the Allies have so many shipping problems they can't/wont reflag so many ships as Soviet for the Vladivostok lend lease route.

The July 43 OTL Atlantic U-boat defeat will pretty much end all this anyway then its business as usual for the Allies.

The practical results of this will be that the WAllies need to do *something* to convince the USSR their alliance is genuine. Lend-Lease, especially via a route Japan does not want to interdict even if technically feasible for it to do so, would remain the most viable means of that for a longer time (well, that and an increased effort for the short term with the CBO). If Japan were interested in pursuing a war with the USSR, using its subs would be a moot point in the first place, thus......
 

sharlin

Banned
The Italians did deploy subs to the Atlantic at the request of the Germans and of the sides involved in WW2 they were only second to the Germans in terms of tonnage sunk but suffered accordingly with something like 90% of the subs sent to the atlantic being sunk.

The IJN's subs were not really built for merchant warfare, yes they were big, fast and well armed but they handled like trucks, dived about as fast as a granny with a zimmerframe walking down a path and there simply wasnt enough of them, and their performance when under attack by US sub hunting groups shows they would have had issues against well trained escorts.

Also the IJN's 'intelligence' gathering was abysmal. Worse than the German's attempts to get a spy ring in England (you know the 100% failure rate...) The Japanese as a whole seemed to take intelligence organisations as folks who guessed lots and sometimes got lucky, and thats how the Jap's operated their intelligence. They assumed, second guessed and downright made things up and then belived what they said and made it canon.
 
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