In American politics, even presidential power has its limits. And now, the laws of political gravity may finally be catching up with Donald Trump’s hyper-aggressive exercise of executive authority. Following what political scientist Ian Bremmer describes as the most consequential electoral reversal for a governing party in more than half a century, the founder and CEO of Eurasia Group and GZERO Media argues that the United States has entered a new political phase: the beginning of the end of Trump’s ability to dominate the political agenda, at home and on the world stage.