On the anniversary of the Capitol insurrection, America has only grown more divided. More Republicans than ever believe that the election was stolen. And that’s not just a domestic problem. It’s a national security threat. Ian Bremmer speaks with Fiona Hill, former senior director of the National Security Council who famously testified against her boss, former president Donald Trump, in his first impeachment trial. Hill, an expert on Russia and China, worries about the global implications of January 6.