Is there any doubt about Osama bin Laden’s position on the not-at-ground-zero mosque? Osama abhors the vision of interfaith harmony that the proposed Islamic center represents. He fears Muslim clerics who can cite the Koran to denounce terrorism. It’s striking that many American Republicans share with Al Qaeda the view that the West and the Islamic world are caught inevitably in a “clash of civilizations.” Anwar al-Awlaki, the American-born cleric who recruits jihadis from his lair in Yemen, tells the world’s English-speaking Muslims that America is at war against Islam. You can bet that Mr. Awlaki will use the opposition...