Russell Moore nicely summarizes the Wilson-Hitchens Debate: “Throughout the debate Wilson challenged Hitchens as to the foundational basis of his ongoing moral judgments. Hitchens seemed to misunderstand Wilson’s point as being that an atheist couldn’t be moral while Wilson, echoing Romans 2, repeatedly reasserted that, no, the issue is that an atheist cannot account rationally for his morality.”
Wilson is warm, cogent, and persuasive. If you want to better defend the reasonableness of the Christian faith to atheists and agnostics, I highly recommend this debate.