The bottom line is - if you want to be a pacifist, you need to take more of an active, engaged and informed role in politics. Standing on the sidelines while things are set in motion and then refusing to get involved isn't good enough - you should have been involved earlier to prevent them if you genuinely care about life.
Another broad stroke or painting with a wide brush statement. I'm not a political involved person I have very little interest in it, only around election time does my interest go up a little, and times of say national crisis. But I do agree if a person feels strongly about an issue they should take the kind of action you describe be it protesting in the streets and what not. Civil disobedience or non compliance is also another course of action too.