There is in the Old Testament a lot of concern about a promised land and how to get to that land. The Jewish community continues to declare that all of the land in Israel is their land. The early Christians were told that their’s were “a chosen nation.” In the New Testament, “nation” was given a larger meaning. A nation was being a part of the community of believers, and not a specific piece of land. The Kingdom of God was a kingdom of faith and not political identity. The devotion to one piece of land, one political party, or one particular race of people has very little support in the New Testament. All those who are of like mind and faith are part of the nation, the kingdom, the new people.
The continuous rise of the alt-right parties, the growing nationalism that is worried about one country and only one country, seems to me to be running in the exact opposite of the theological convictions of the New Testament. There does not appear to be any religious or theological basis for the borders of any country. Paul suggest that it is wise not to disobey the political powers, but other than saying political powers are necessary for an orderly society, he does not proclaim any country or nation as necessary. The creation of nations is a human construct. The boundaries of almost every nation has been changed, enlarged, shrunk, or divided throughout the course of history. There are no religious reasons for the devotion to one country over another.
There are some fundamental theological convictions which seem to be in opposition to nationalism. The earth is the Lord’s seems to mean that all creation is God’s and so he care for it all. No nation has or deserves any special privileges or rewards. All land is sacred land. All people in all nations are God’s people and God’s creation.
Those who wanted to be known as Christians in the early church found themselves being persecuted by the Roman government because they would not swear allegiance to the Emperor and acknowledge the Emperor as a god. Over and over throughout history in all kinds of nations, those who claimed to be followers of Jesus found that they were persecuted by the government. The allegiance of Christians is to the Kingdom of God and any and all loyalties to a nation which has been made made is idolatry.
The British exit from the EU, the “America First” of our current president, the rise of the alt-right in France are all examples of the betrayal of the Christian faith by many who think they are the faith greatest warriors.