Just Curious But How Many U-Boats Can You List

[Paciat]

Yes if I were the Germans I would rely on the FRENCH and the Italians, the worst allies someone could have.

You would have to. Or you can try and take Giblartar.

The Germans invested heavily in their submarines because they knew their surface fleet couldn't stand a chance, the U.S. was able to attain such success because the japs didn't believe in a strong underwater force because their surface fleet already rivaled the U.S.

Youre wrong.
Japanese belived in a strong underwater fleet before the war and used their subs to attack the navy becouse of that. Most navies belived that subs are very fragile and all they can do recon or sunk merchant ships. Merchant ships cant defend and you dont need a strong force to take them on.
Germans invested in U-boots while UK invested in commando/SAS raids (1940-1943). Both could never stand up to the might of Wehrmacht/R. Navy and win the war alone.

[Griptonix]

The Kriegsmarine didn't have to use only their own merchant ships, they did conquer a significant number of countries that border the Mediterannean, thus giving them not the French or Italians more responsibility in supplying their own Afrika Korps themselves.
If the japs did invest heavily in it, why didn't they have they experience the success that a nation like germany did? they suffered similar losses and size of the fleets

[Paciat]

If the japs did invest heavily in it, why didn't they have they experience the success that a nation like germany did?

As Ive said before, Japanese focused on sinking the US battlefleet.