God in America explores the post-World War II era, when rising evangelist Billy Graham tried to inspire a religious revival that fused faith with patriotism in a Cold War battle with Godless Communism. Conservative evangelicals' embrace of presidential politics ends in disappointment and questions about mixing religion and politics. New waves of immigrants from Asia, the Middle East and Latin America make the United States the most religiously diverse nation on earth. In the 2008 presidential election, a religious voice reemerges in the Democratic Party.