Democratic norms are self-reinforcing: when politicians follow them, they strengthen them, and when they break them, they weaken them. This explains why Trump’s actions are likely to have ripple effects and exacerbate polarization in the long term. Levitsky and Ziblatt also distinguish between useful and dangerous presidential norm-breaking. Their litmus test for whether norm-breaking is useful is whether it promotes or harms democracy. Carter and Harrison’s decisions brought them closer to voters, while Roosevelt’s was an important step towards racial inclusion. But Trump’s “lying, cheating, and bullying” undermined key norms that make democracy function. He didn’t just attack toleration and forbearance, but also more basic norms like civility, honesty, and respect for the truth.