Cracks in the Republican Party’s façade of unity are showing. Trump stumbled into the New Year, having invited a shutdown of the federal government, prompted the resignation of Defense Secretary James Mattis, suffered through the stock market’s worst December since the Great Depression, and watched his nemesis Nancy Pelosi assume the speakership of the House. Susan B. Glasser joins Dorothy Wickenden to discuss whether Trump faces any significant dissent from within the congressional G.O.P., and what it would take for the Party to abandon a President who retains the same approval rating he has held since taking office.