This is part of Hello, Trumpworld, Slate’s reluctant guide to the people who will be calling the shots now—at least for as long as they last in Washington. When Donald Trump first got to Washington in 2017, New York Rep. Elise Stefanik was commencing her second lap in Congress as a tough-talkin’ Republican moderate. That year she openly criticized Trump for withdrawing the United States from the Paris climate accords and reproached him for the Muslim travel ban. But Stefanik is a quick study—she went to Harvard, after all, and was elected vice president of the school’s Institute of Politics...