Difference is, I suppose, is that we are not in a state of war...piracy is a criminal act!
BTW - how effective were DEMS vessels and did they make a significant contribution?? I ask this because my wife's uncle, 2nd Mate on a tanker, was responsible for the defensive armaments. He was manning the aft conning position (where fire control was based) when the whole stern was removed in a torpedo attack. His brother was also lost on 100 Sqn, after the fall of Singapore.