I just finished listening to Campolo and Gary Bauer in a debate over the Christian response to the War on Terror. If anything, it highlighted to me just how hard the questions are. A Christian's interaction with the state is indeed a precarious thing.
At one point it was making me think how divorced from each other the New and Old testaments of the Bible seem to be. But as I re-think that, I can see that what they hold in common is the notion of human beings humbly handing control over things back to God. In the Old testament, it was done by believing in him to fight the battles, to the point of doing humanly ludicrous things like shrinking your army down to a force of 300 to prove that it was God who was really fighting the battle. In the New testament, it was a rejection of force and violence to the point of giving up your own life, if necessary.
I wonder, then, if a modern day goverment could ever dare to truly go either way. I think I might be kind of impressed with the American government if they said, look, this is how we are going to fight the battle. God is on our side and he will give us the victory, so we are not going to do it on our own strength. We will send a handful of priests and pastors to march around Baghdad, and God will strike all the bad guys dead. Never happens, does it. A friend of mine points out that, if we are going to embrace the OT model, it might in some cases require us killing every man, woman, and child we conquer. Yeesh, this option is getting less and less attractive.
The other side of the coin seems even less possible. Can you imagine a New Testament nation, a nation of Christ-followers? Similarly, we would declare that God is in control, so our military efforts would be completely unnecessary. Our weapons would be prayer, kindness, and compassion, blessing our enemies with the good things that have been given to us (wow, one wonders what effect that would have in the spiritual realms). Our job would be to live as Christ instructed. The outcome would be entirely in God's hands. It really comes down to the degree to which we trust God to be in control.
I don't know if I believe in the possibility of a "Christian nation". Perhaps we are meant to be "aliens and strangers", a political threat to the nations we are in, simply because our allegiance is not to that nation. But I do believe in the second coming of Christ, and I believe that therein we will discover how a "Christian nation" should really be done.
For Christians looking for a biblical response to war, these are really the only two options that scripture gives us. Funny that we take neither of them very seriously.