After meeting Donald Trump for the first time, in New York on Dec. 6, Rex Tillerson told his wife, Renda, that the president-elect had offered him the job of secretary of state. Tillerson had spent his entire 41-year career at Exxon Mobil Corp., the previous decade as chief executive officer. His assets are worth an estimated $400 million. He’d planned to step down in the spring of 2017 and retire to a ranch near his hometown of Wichita Falls, Texas. Few people close to Tillerson believed he was destined for government service, except his wife. “You didn’t know it, but you’ve been in a 41-year training program for this job,” she told him. “You’re supposed to do this.”

Tillerson recounted this conversation in his welcome remarks to a few hundred Department of State employees on Feb. 2, the day after the Senate voted to confirm him. The story drew laughs and a round of applause. Tillerson’s plain-spoken, shirt-sleeves style calmed the nerves of the diplomatic corps, which had been routinely pilloried by Trump and his hard-right advisers. “You have accumulated knowledge and experience that cannot be replicated anywhere else,” he told the crowd jammed into the department’s C Street lobby. “Your wisdom, your work ethic and patriotism, is as important as ever.” His charges had reason to believe that with a pragmatic corporate titan in command, the department would reassert its primacy over American foreign policy—and ease global anxieties about the new president’s nativism, naiveté, and flirtations with noxious strongmen.