Donald Trump launched an extraordinary attack Monday on outgoing British premier Theresa May, following the leak of diplomatic cables highly critical of his presidency. London has been scrambling to stem the damage caused by the weekend release of confidential telegrams in which its envoy to Washington, Kim Darroch, described the US leader as “inept†and his White House as “uniquely dysfunctional.†Visibly angered by May’s continuing support for her ambassador—which Downing Street r