Is America a Christian Nation?

I'm asking the question because it's in the news today. Our President (who's ON NOTICE with me, you might remember) is in Turkey, a Muslim nation, telling them that we are NOT a Christian Nation. " And I've said before that one of the great strengths of the United States is -- although as I mentioned, we have a very large Christian population, we do not consider ourselves a Christian nation or a Jewish nation or a Muslim nation; we consider ourselves a nation of citizens who are bound by ideals and a set of values."
http://blogs.suntimes.com/sweet/2009/04/obama_and_president_gul_of_tur.html


This quote is from a Newsweek article that came out Saturday
"It was a small detail, a point of comparison buried in the fifth paragraph on the 17th page of a 24-page summary of the 2009 American Religious Identification Survey. But as R. Albert Mohler Jr.—president of the Southern Baptist Theological Seminary, one of the largest on earth—read over the document after its release in March, he was struck by a single sentence. For a believer like Mohler—a starched, unflinchingly conservative Christian, steeped in the theology of his particular province of the faith, devoted to producing ministers who will preach the inerrancy of the Bible and the Gospel of Jesus Christ as the only means to eternal life—the central news of the survey was troubling enough: the number of Americans who claim no religious affiliation has nearly doubled since 1990, rising from 8 to 15 percent. Then came the point he could not get out of his mind: while the unaffiliated have historically been concentrated in the Pacific Northwest, the report said, "this pattern has now changed, and the Northeast emerged in 2008 as the new stronghold of the religiously unidentified." As Mohler saw it, the historic foundation of America's religious culture was cracking." http://www.newsweek.com/id/192583

I believe that we are a country founded on Judeo-Christian principles. I believe we have been in the past and are now a Christian Nation. I believe that we need to do all we can to hold on to that before we are just a country who used to be a Christian nation before we became "enlightened." This does not mean I believe we should be a theocracy. Evangelism, anyone? What do you think?