One of the founding principles of the United States is that religion and politics, church and state, are separate. Yet today in America religious belief and politics have become inseparable. Self-styled "evangelical" Christians have become the dominant grassroots force in the Republican Party. "Evangelical" is not a denomination, it can mean different things to different people in terms of religious doctrine. The unifying principle seems to be in the political outlook of its adherents: deeply conservative in the 21st Century American political context. Michael Goldfarb explores the tension between a life of Christian faith and the dirty realities of secular politics.