Peter Leithart said this quote

A Christian who is willing to take up arms against another Christian is a Christian who has traded in his membership in the post-Babel communion of saints for membership in a nation governed by refurbished stoicheic values. They have traded in their loyalty to the temple of the Spirit for loyalty to the flesh. Christians who make war against other Christians are Galatians, bewitched by the lure of patriotism, which is simply the lure of flesh. They are no longer in the ranks of the Spirit.