The heartbreaking violence in the Middle East, Ukraine, and elsewhere carries many messages, but here’s one Americans shouldn’t miss: The United States — no matter who the president is — cannot manage world conflict. The corollary is that when a president tries to manage it, things will usually get worse. Foresight is always defective, and tragic unintended consequences will prevail. The foreign-policy “experts” in both major political parties, and the intelligentsia generally, think...
