President Donald Trump criticized his Democratic presidential rival, Joe Biden, on Tuesday evening for failing to enforce a national mask mandate — but Biden, as a candidate, has no authority to do so. Trump leveled the attack after being asked by a voter during an ABC News town hall why he had not supported universal mask-wearing. "A good question is, you ask, like Joe Biden. They said, 'We're going to do a national mandate on masks,'" Trump said Tuesday evening. "But he didn't do it, I mean, he never did it." Trump was referring to a policy promise that Biden...