Although I stand on opposite polls of the political and ideological spectrum from Virgil, I agree that war is simply a fact of statecraft. It's not about whether war is justifiable or good, but it's a necessity. Historically, it has been reluctance to intervene more than over-eagerness that has led to the most catastrophes. How much better off would the people of Rwanda have been if the UN Peace Keepers were given the go ahead to seize the military weapons cashes in Kigali, instead UN headquarters told them to stand aside and just try to shelter a few civilians as long as they could, and even that was deemed too risky when a few Belgians died.
Military force is something we shouldn't use without great consideration, but is something we occasionally have to and should use. Pacifism is fine as a political strategy in a functional democracy, but it does little to stop the local crack head from stealing your TV, or to stop the neighbouring dictator from annexing Czechoslovakia.