I appreciate your reply and would like to make a few comments.

Concerning the history angle I agree with you in a sense. It is indeed very inportant to understand the history of a thing in order to form ideas about it.
Our nation is apostate. And I agree that we should not be swearing oaths to it. But then again, all Western thought is apostate, not just our nation. So what do we do about it? As you said we must testify against it. But as Pilgrim mentioned we need to be very careful that we don't embrace the Reconstructionist movement. Until Christ himself comes to live with us on The New Earth there will not be a nation that is not apostate.
Personally I consider myself to be a citizen of The New Jerusalem. I will not say "The Pledge of Alligence" because I think it is a prayer, and I literally don't want to be caught dead praying to that god.

On your comment about pragmatism. You have really hit the nail on the head there, maybe even more than you know. Since the French Revolution (modernism) the "gods" that control Western philosophy are pragmatism and rationalism. Our whole worldview is shaped by those "gods". As Christians we need to develop a different worldview. One that places Christ at the center of our philosophy. (This is different than theology).
I can see that you have a burning desire to be faithful to Christ in all areas of your life. That is a fine thing. Praise and thank God that he has given you that blessing.

For further study on how a Christian should respond in the public sphere check out this website: http://www.cpjustice.org
This organisation actually wields some influence in Washington. It's stated purpose is "a comprehensive Christian political foundation", without being involved in Theonomy (Reconstructionism).
Also run a Google search for two men who strived to form a Christian philosophy. Both are in the reformed tradition.
Van Til
Dooyeweerd
It's heady stuff, and a bit over my head. I am not a scholar but have come to realize that these issues are important for all Christians. So I try to wrestle with it and understand as much of it as God will allow.

Blessings on your journey.