A must-read post from Roger Olson:
What about Christian attitudes towards the American empire today? Can we be proud to be American in spite of many things about America today with which we must disagree and which we must criticize if not condemn? I don't see why not.
However, we must learn to do two things with which the ancient Christians of the Roman Empire struggled.
First, we must learn to draw a line between loyalty to and good citizenship of the empire (nation-state and its territories and commonwealths) and uncritical accommodation to its ways of life and its customs, habits and acceptance of all its treatments of others. Uncritical "Americanism," nationalism, is tantamount to idolatry. America never was and never can be "God’s nation."
Second, we must learn to draw a line between true Christians and false Christians. All of the ancient church fathers searched for that line and found it in an implicit then explicit "rule of faith" (Irenaeus and Tertullian) and supreme loyalty to the way of Jesus Christ as different from the ways of "this world." "Christians” who succumbed to the ways of this world such as materialism, greed, oppressing the poor and weak, militarism, idolatry and hatred were expelled from the church and when that could not be done (e.g., when they were emperors or their surrogates from Constantine on) they were harshly criticized from pulpits (Chrysostom and Ambrose) and even denied the sacrament of communion (eucharist).
The entire post can be read here.