So what is it about liberalism that makes it so difficult for it to take a clear, critical look at Islam, even while liberals have no problem excoriating Christians for every imaginable historical evil? I believe I can give at least a partial answer, if we take a big step back from the present scene and view the history of Western liberalism on a larger scale. Liberalism is an essentially secular movement that began within Christian culture. (In Worshipping the State, I trace it all the way back to Machiavelli in the early 1500s.) Note the two italicized aspects: secular...