Ezra Klein: Democrats, repeat after me: Help people first

President Joe Biden takes office with a ticking clock. The Democrats’ margin in the House and Senate couldn’t be thinner, and midterms typically raze the governing party. That gives Democrats two years to govern. Two years to prove that the American political system can work. Two years to show Trumpism was an experiment that need not be repeated.Two years.This is the responsibility the Democratic majority must bear: If they fail or falter, they will open the door for Trumpism or some