WASHINGTON (AP) — NATO leaders are gathering in Washington this week as the military alliance confronts the prospect of the return of NATO skeptic Donald Trump to the White House. The summit kicks off Tuesday and heads of state will work to shore up transatlantic support for Ukraine in its battle against Russia. But for host President Joe Biden, it’s just as much about demonstrating he’s capable of meeting the grinding demands of the presidency for four more years. The president said his work at the summit would be a good way to judge his continued ability to do the job. His reelection campaign has been in a tailspin following a disastrous June 27 debate performance against Trump.