AP Photo

The truth about Chuck Hagel is that he saw before most that America was embarking on an unparalleled strategic disaster by diverting its attention from al-Qaida a decade ago. He saw, and had the courage to say, that his own president and party were failing to anticipate the enormous cost of going into Iraq and of losing focus in Afghanistan. He saw that Bush was isolating himself by inventing an entirely new war that both defied world opinion and—in another enormous strategic misconception—gave al-Qaida new life by vindicating Osama bin Laden’s once-unheeded warnings to his fellow Islamists that the real peril was the “far enemy,” the United States. As Hagel divined, by invading Iraq, Bush displaced the dictatorships in Egypt, Saudi Arabia, and other...