Most of Washington expressed surprise when President Trump tweeted that Rex Tillerson will be replaced by Mike Pompeo as secretary of state. Tillerson, who just returned from a five-country tour of Africa, learned that he’d been fired as most of the country did. Senior officials in the administration and Congress say they were blindsided by the decision. The former oil executive’s short stint has exposed the ad-hoc nature of President Trump’s foreign policy.

The State Department has been woefully understaffed. Several posts remain empty, including top diplomats in some of the most volatile countries. Last fall, President Trump declared that when it comes to diplomacy, he’s “the only one that matters.” That came shortly after Tillerson allegedly called the president a “moron.” Tillerson supposedly never wanted the cabinet position, but in January, he assured reporters that he’d remain secretary of state through 2018. To discuss the State Department shakeup, we’re joined by Stephen Walt, professor of international relations at Harvard University.