Tommy Robinson, Britain’s self-styled free speech warrior, has been allowed to enter the U.S. despite a long criminal rap sheet. On Thursday, Robinson, whose real name is Stephen Yaxley-Lennon, posted a video on social media from an airport in the U.S. announcing, “I’ve arrived!” He said the trip was “last-minute” after he’d been informed only hours earlier that he’d gotten a visa, and hinted at plans to throw himself into U.S. politics. That apparently included a meeting with Donald Trump’s former national security adviser Michael Flynn, a longtime peddler of MAGA election conspiracy theories. Sharing a photo of himself shaking...