Nagasaki Bombed Sixty-Six Years Ago/US Sends Representative to Commemerate

Sixty-six years ago, today. Apparently, the US sent a representative to commemorate the bombing.

I don't really care if we send someone to go to the commemoration or not, but I'm not really sure what the point is. Are we saying that we're sorry, or are we trying to put the war behind us and build relationships going forward? Or something else?