read this:
"One of the great difficulties is to keep before the audience's mind the question of Truth. They always think you are recommending Christianity not because it is true but because it is good. And in the discussion they will at every moment try to escape from the issue "True--or False" into stuff about a good society, of morals, or the incomes of Bishops, or the Spanish Inquisition, or France, or Poland--or anything whatever. You have to keep forcing them back, and again back, to the real point. Only thus will you be able to undermine...their belief that a certain amount of "religion" is desirable but one mustn't carry it too far. One must keep on pointing out that Christianity is a statement which, if false, is of no importance, and if true, of infinite importance. The one thing it cannot be is moderately important."
CS Lewis God in the Dock
I agree with Lewis, as if that added anything to the discussion. We are in the world but not of the world, however we are to redeem and use the world's systems and materials to advance the Kingdom, such as money, jobs, education,political systems, management systems, communication systems and defense systems etc. The difference is in the verses from Romans 12 that you quoted. It is by the living sacrifice and the renewing of our minds that we redeem the systems for the Lord's use, not the worlds and by that, robbing the enemy of his own tools.
By the way, I haven't thanked you for posting this article and getting us off of the other threads on Luther and Wheaton that have been going around in circles for the past two weeks. It is refreshing to be debating old chestnuts. I am indebeted to you.