It is often said that the roots of the Holocaust can be seen in these medieval pogroms. That may be. But if so, those roots are far deeper and more widespread than the Crusades. Jews perished during the Crusades, but the purpose of the Crusades was not to kill Jews. Quite the contrary: Popes, bishops, and preachers made it clear that the Jews of Europe were to be left unmolested. In a modern war, we call tragic deaths like these “collateral damage.” Even with smart technologies, the United States has killed far more innocents in our wars than the Crusaders ever could. But no one would seriously argue that the purpose of American wars is to kill women and children.