President Trump plans to kick his “America First” doctrine up a notch, foreign policy experts are saying. Now that U.N. Ambassador Nikki Haley has announced her resignation at the end of the year, Trump is said to be gearing up for a hard-line shift on foreign affairs. Foreign diplomats are fretting a new “hard-line unilateralist to replace Haley,” said one foreign policy wonk. Speculation about that ramped up when Trump quietly decided to move up Haley’s departure so he could name a successor within three weeks that can be confirmed by a Republican Senate.