The Bomb: Presidents, Generals, and the Secret History of Nuclear War

by Fred Kaplan

In short, Mattis didn’t think there were any good military options in Korea, and he didn’t want to foster the illusion that there were. Mattis’s resistance infuriated McMaster, who was Trump’s point man on the task. The two officers did not get along. As the president’s national security adviser, McMaster thought he should be regarded as an equal by the secretary of defense, but he felt that Mattis treated him the way a four-star general treats a three-star—as a subordinate. McMaster too had been a decorated wartime commander—the leader of a tank squadron in the first Gulf War, a master counterinsurgency tactician in the Iraq War—but he never commanded a unit larger than an armored cavalry regiment, which consisted of about 3,500 troops. By contrast, Mattis had been commander-in-chief of U.S. Central Command, overseeing 200,000 personnel from all the services in military operations across the Middle East, North Africa, and South Asia. Mattis had also been senior military adviser to a secretary of defense, while McMaster had no prior Washington experience.