Several doubtful points in the naval battle of World War II, with high scores.

There were indeed many submarines in Britain, France and the Soviet Union during World War II, but they were all evaluated as mediocre by history. It's not that their submarines can't work, but that their submarines are too small. Using submarines to deal with warships is basically equivalent to suicide. The submarine was bitten by a warship, so it is best to use it to harass the local logistics supply line. Even if the submarine is used, it can't cooperate well, can't cooperate with air and water forces, and is not easy to mobilize. These are the reasons why submarines rarely participate in fleet operations. In World War II, except for Germany's wolf tactics, most other countries allowed submarines to act alone. Only Japan was stupid and used submarines to deal with allied warships, resulting in very heavy losses and becoming a big joke.

The sinking of Japanese aircraft carriers by American submarines mostly relies on a big luck or an ambush. This tactic is too lucky to be used as a conventional tactic, and there is a great chance of failure. Both air power and surface ships can be used to win, even if the cost is higher, because this is war.

German carrier-based aircraft originally wanted to use BF 109, and there were plans to develop carrier-based aircraft specially, but they all went away. Even if it was really built, it should be BF 109.

At that time, Germany's technology was really advanced, leading the world 100 years, which is an exaggeration. But at that time, Germany's scientific theory should have been ahead of the world for a hundred years, and some of them are now in the verification stage and cannot be put into practice.