US ambassadors to UN

Donald Trump at the Conservative Political Action Conference in 2011 in Washington. As president, he has let the US ambassadorship to the UN, the country’s second-most important foreign policy role, sit empty for months. GAGE SKIDMORE/CREATIVE COMMONS

Nikki Haley, the US ambassador to the UN, in the Security Council chamber, Oct. 18, 2018. She left a bruising mark on the UN, having criticized it constantly and lectured other countries, yet some of her peers admired her. RICK BAJORNAS/UN PHOTO