In a weak democracy, an authoritarian leader like Trump could do widespread and lasting damage. Such leaders often control the legislature, are immune from court oversight, and suppress civil society institutions. But our hallowed traditions of judicial independence, civil liberties, and a robust political culture have—thus far, at least—held Trump in check to an important degree. The courts cannot stand up to President Trump alone, however, and it would be a great mistake to think they could. In the end, the most important guardian of liberty is an engaged citizenry.