Democracy has been resilient for a long time, but that doesn’t mean it can’t reach a breaking point. Social media is an unprecedented challenge: In every way, it represents the Founders’ nightmare. Madison wanted to slow down communication to allow for thoughtful decision making; social media encourages instant responses and emotional, ad hominem arguments. Madison worried about factionalism; social media encourages it. More than any previous communications technology, social media has the effect of herding users into likeminded communities where they never have to hear an opposing point of view. In a 2020 article in Science, 15 psychologists and political scientists wrote that America’s political divisions were being amplified by “popularity-based algorithms that tailor content to maximize user engagement.” If the Founders had been able to spend an hour on X, they would have been a lot less optimistic about human beings’ capacity to govern themselves by reason rather than passion.