After Syrian leader Bashar al-Assad launched a chemical attack on civilians in April 2017, Trump called Mattis and said he wanted to assassinate the dictator. “Let’s fucking kill him! Let’s go in. Let’s kill the fucking lot of them,” Trump said, according to Woodward.

Mattis told the president that he would get right on it. But after hanging up the phone, he told a senior aide: “We’re not going to do any of that. We’re going to be much more measured.” The national security team developed options for the more conventional airstrike that Trump ultimately ordered.