A very common mistake. Pacisfism is not a tenet of Christianity (see the thread on this in the southern forum, as I don't want to have to write it all out again).
Now is being involved in a war a great strain on your faith? Absolutely. It's incredibly difficult not to hate the guy who's shooting at you, and psychologically it's pretty difficult to extend agape to the guy you're shooting at.
"The man who stands for nothing is likely to fall for anything"
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