From the moment Donald Trump was elected President, critics have anguished over a breakdown in constitutional norms. History demonstrates, however, that constitutional norms are perpetually in flux. The principal source of instability is not that these unwritten rules can be destroyed by politicians who deny their legitimacy, their validity, or their value. Rather, the principal source of instability is that constitutional norms can be decomposed—dynamically interpreted and applied in ways that are held out as compliant but that limit their capacity to constrain the conduct of government officials.

The paper calls attention to that latent instability and, in so doing, begins to taxonomize and theorize the structure of constitutional norm change. We explore some of the different modes in which unwritten norms break down in our constitutional system and the different dangers and opportunities associated with each. Moreover, we argue that, under certain plausible conditions, it will be more worrisome when norms are subtly revised than when they are openly flouted. This somewhat paradoxical argument suggests that many commentators have been misjudging our current moment: President Trump's flagrant defiance of norms may not be as big a threat to our constitutional democracy as the more complex deterioration of norms underway in other institutions.