In the case of your examples Les, I would agree as they were events that took place on a single day. BUT, in the case of the Great War this happened over a period of 4 years and the point I am trying to get across is, that at the beginning of the war, there were NO casualties and nobody could have predicted how bad it was going to be. So it is odd commemorating an event because lives were lost after the event.
I would describe myself as more anti-Cameron than anti-Tory, but what other reason could have motivated him to commemorate something four years too early?