How can the act itself be seen otherwise? Imagine the Japanese PM visiting Pearl Harbor. He can either a) apologize b) gloat c) remark it was different times or something and it was unfortunate what happened. Like DKR said about the forward pass, there's three possibilities and two are bad. If he goes there he's obviously not going to celebrate what happened. If he says it was tragic or devastating or proof that nuclear weapons are bad that is a pseudo apology. If he apologizes outright that's obviously an apology. So two of the three are saying sorry.