Show me in the scriptures, where a Christian in the NT defended their country? Or is commanded to defend their country?
Now as an American I can, but that has absolutely nothing with being a Christian. That is not our primary duty, it is our American duty.
BTW gospel preaching churches are never commanded to get into politics or defend any nation. They are to preach the word of God and win the lost to Christ.
Now if you have some scripture that says otherwise, let me see it