This is a day about which I have profoundly mixed feelings. Both of my grandfathers served in WWII; one in the navy in the Pacific, the other in the army medical corps (though I'm not sure if he was ever out of the country, as he was still finishing his MD during the first years of the war). I'm fairly certain that one of my uncles served during the Vietnam War, though at least one other was a conscientious objector (my father was in grad school, and then I think too old for the draft).
The fact that I say "at least" is an indication of how little such service is discussed in my family. I do not think I have ever heard either grandfather or the one uncle talk about their experiences. They served, they survived, and they don't want to dwell on it.
So while on the one hand I do respect veterans for having served, by choice or not, and risked their lives in that service, on the other hand, I think it's a shame when their military service becomes the defining thing in their lives afterward... because war is about killing, when it comes right down to it, and I don't think it's justified whether in war or in the operations of justice. I'm more or less a pacifist, and it seems to me that killing other people is a pretty stupid way to solve a disagreement. By extension, honoring those who do the killing is to me just a little questionable.
I'm not trying to say that my feelings on this are better than anyone else's, or that it's wrong to celebrate this day and honor veterans. I'm just trying to parse out why I personally am neutral about this particular holiday.