the nation-state of war and peace

I've been thinking a lot about an idea from Hannah Arendt's Thinking Without a Bannister - the system of nation-states operates with an understanding that war is the last resort. It's an easy idea to understand if you consider how a country would respond if it became unable to trade for a necessary good, like food. What I'm wondering about is what pacifists think about this idea in the context of nonviolent beliefs, as they might contradict with the above if they retain some commitment to a nation-state system.

The end of war is perhaps too lofty of an ambition in the present day, where the most powerful nation on Earth can make a national goal of putting people on the moon yet can't ensure the equality of any two randomly selected members of its citizenry, but I do think someday the human race will turn its attention to this vital task. Those of us who claim to be ahead of the times must commit in the small ways available today - championing open borders, rejecting the free market as a tool for allocating basic necessities, and reserving the use of nationality only for situations where there is no other alternative.