To say the international environment has become more challenging is an understatement. China, Russia, and North Korea explicitly challenge American leadership, and they aim to erase America’s military lead. Iran and its proxies have been wounded by recent attacks, but they also wish to degrade American power. The U.S. must up its game in appropriations, technology, rapid acquisition of new weapons, shipbuilding, training, doctrine, and recruiting. Equally important is the sound preparation of new officers at the Air Force Academy, West Point, and Annapolis. Three history courses are...