On Sunday, May 17, members of the Trump administration will participate in “Rededicate 250: National Jubilee of Prayer, Praise & Thanksgiving,” a nine-hour prayer festival on the National Mall in Washington, D.C. The purpose of this festival is to call for America to rededicate itself to its Christian roots. So, for what feels like the millionth time, a chorus of researchers, historians, and journalists all repeat: America’s founders didn’t want it to be a Christian nation.