I am all for peace and sometimes it really makes me sad that society hasn't grown past the point of killing each other to solve our differences. That being said there are things that are worth dying for.
You know, we already are solving most of our differences peacefully.
It's differences like
X: "All of Y must die."
Y: "No."
that are impossible to solve peacefully.
As I said before, the compromise between Israel's destruction and Israel's existence is three million dead Jews. Any solution not involving war would either be a compromise or require one side simply to give up.
Nobody is for war just like nobody is for cutting open a life body and removing the appendix just for the heck of it.
"Peace activists", aka those whose ideological goals are not aligned with those of whoever is currently winning a given war, are not really peace activists. (Someone who'd prefer Saddam killing Kurds over the invasion of Iraq are not in favour of peace over war. They just prefer other wars.)
Real pacifists are the equivalent of people rejecting operations for religious reasons, except in as much as it requires other people to fight so the pacifist can be a pacifist.