What is interesting here is that the first followers of Jesus were pacifists- "Live by the sword, die by the sword", and all that. It was only later that Constantine had a vision that said "In this sign, you will conquer" and had crosses painted on the shields of his soldiers (Who of course won), and then down the line we had crusades and holy wars, and the concept of "just war", which of course at a time was meant to be a restriction on war, not to justify it, but to minimize it, but now we're starting to think that maybe even it was too lenient, and perhaps the first Christians had it right after all. It's a very interesting evolution.
I don't know that Pope Francis is a pacifist, but I do know that both Pope John-Paul II and Pope Benedict rejected the Iraq War as unjust, and Pope Francis seems to be to the left of them, so maybe we're getting close to that territory.
I don't consider myself a pacifist, but I think peace is the ideal state, right? Even if only in an abstract idealistic sense that I might not always apply to conditions on the ground, so to speak. Though I was also against the Iraq War. But I do think some wars need to be fought- wars in self-defense, etc.- like going into Afghanistan after 9/11, or fighting the Axis Powers after Pearl Harbor. But in a sense maybe all of that is a concession to human weakness.
It's an interesting subject. There's a certain power in not playing the game, and peacefully resisting evil instead- it worked for Ghandi in India. Of course, sometimes when you do that, they just roll over you in tanks- like the protesters in Tienanmen Square (China) in the late 80s.
I would certainly say that we should exhaust all options for peace before considering war and not in a phony George W. Bush Iraq War kind of way- really, make sure *all* the options are exhausted.