This is a very good article.

A Christian and a Patriot?

But the United States is a very different case. The U. S., it just so happens, was founded largely to fulfill just the sort of pro-liberty, non-interventionist role the Bible envisions.  The Founders, whatever their flaws, were to the man, dogged defenders of religious liberty.  Although some of them were influenced by a conservative Enlightenment rationalism, most were professing Christians (see the extensive evidence presented in M. E. Bradford’s "Religion and the Framers").  This is why they did not establish a national church — they did not want to disturb the various states’ established Christian churches. This is why they produced a federal Constitution, which elaborately checked sinful men’s insatiable lust for power, including the sinners who happened to be politicians.  This is why they drafted a Bill of Rights, which jealously guarded religious liberty. This is why they wrote that one of the nation’s great objectives is “to provide for the common defense.”  As Eric Hoffer once said, this nation was founded by people who basically wanted to be left alone.   This just happens to be the sort of civil government the Bible demands we pray for.

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There are big checks on power in this country, because the Founders operated in terms of Christian ethos — men are sinners.

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Christian patriotism in the United States is necessary because it cultivates and defends the sort of minimal civil government that the Bible requires.  We are patriots not because we have a love affair with the United States as such; we are patriots because the principles on which the nation were founded allow Christianity to flourish.  The United States is first about ideas, and those ideas are, for the most part, Christian ideas. On this basis, we can join the flag-waving.