The Pentagon is not Boeing. At a company, orders can be given and followed; policymaking is top-down, as Shanahan demonstrated when called on by management to fix an ailing Dreamliner program. Politics in a federal government agency are of a different kind. At the Department of Defense, there are many independent power centers—the collection of armed services chiefs is a big one—that have to be cajoled for defense secretaries to achieve their goals. As one former secretary of defense told me at the start of his tenure: “If I don’t have the Chiefs with me, I can’t run the building.” Outside power centers like the White House have to be worked behind the scenes; Congress has to be flattered and persuaded. Respect has to be earned everywhere.
Unlike for CEOs, defense secretaries’ day-to-day responsibility is rarely to run the department itself. Instead, their job is to be the face of the Pentagon to the rest of the world—other federal agencies, the public, allies, and adversaries—through interagency and White House meetings on policy, congressional testimony, overseas travel, media appearances, and international negotiations. The White House relationship is a particularly important role for the defense secretary, who is one of the four principal national security policy advisors to the president, along with the national security advisor, the secretary of state, and the chairman of the Joint Chiefs of Staff.
This is a task for which departing Secretary of Defense James Mattis was well prepared through decades of military service, including overseas command in Afghanistan and Iraq, leadership of the military’s Central Command, and a turn as NATO commander for defense transformation.