And the carrier donīt shot back ?? :hmm: some thing could be wrong if not.
All carriers have a lot of AA and sometimes small guns, that can shoot and sunk a boat easily or kill the deck crew.Or launch a bomber or fighter loaded with bombs and machineguns.The fleet class submarine are not a battleship.
Remember the main tactic for a submarine, avoid scorts and sunk main targets or warships.
A carrier is very difficult to replace, but not a 1000 ton destroyer.