Most of the German and Japanese submarines were destroyed. The best sub in the world in 1945, was the German Type XXI. If I recall off the top of my head, U-534, U-995, U-505, and U-2540 are the only full sized U-Boats left in the world. But the Germans also came up with the Type XIX and the Type XX, both cargo carrying submarines. There was also the Type XIV resupply sub. In WWI, Germany had the SMS Deutchland. A submarine merchant vessel. Please forgive my bad German.
In WWI the allies used Q-Ships.
Makes me wonder whay happened to all the Japanese, German and Italian minisubs from WWII.
Seems like the Germans were
using their Bibers in late 44 and early 45 to get supplies to cut off units on Western Front.
Some of the German ones were high speed and towed a mine.
The British Xcraft had side mounted large explosive charges.
I came across a rumor some years ago that a drug dealer in Seattle area had a small miniature sub he used to deliver drugs to a stash in the Duwamish River.
FWIW I also remember an Edward Ellberg novel about WWI where a small US sub is towed submerged by a freighter to trap unwary U-Boats.
Hmmmmmm
Larry Murray