An WW2 average merchant ship was less than 10,000 tonnes.
now compare that to todays merchant men which average around 85,000 to 90,000 tonnes you could see that erich topps top score could be beaten with just one sub a hand ful of torpedos and a few days.
there are more merchant ships on todays sea so more tragets there are less warships than in the cold war and also submarines, missiles have evolved to a point where you just shoot and forget, unlike WW2 where you spent hours lining up for a target now you just find it and fire at it then forget.
BTW worlds biggest ship jahre viking is 548,000 tonnes sink that youve just killed the worlds oil trade in one hit
