That isn't true. I watched the interview with one of the guys in that ad on MSNBC and he was talking about being in a boat 50 feet from Kerry and that the guy he saved did fall in the water, but no one was shooting at them at the time. The guy who Kerry saved(I really need to find out his name, lol) was on the show as well and I believe him.
So yes they are attacking what he did DURING the war as well.