The key issue is this: One of the three branches of the federal government has just incited an armed attack against another branch. Beyond the threat to a peaceful transition, the incident was a fundamental violation of the separation of powers. Prompted by the chief executive, supporters laid siege to, invaded, and occupied the Capitol building, deploying weapons and subjecting members of both chambers of Congress to intimidation and violence in an effort to produce a particular decision by force.

We have all been taught about “checks and balances” in school. The Constitutional strategy for limiting power requires that officeholders defend the institutions they occupy against what the framers called “encroachments” by the other branches. Usually encroachments are understood metaphorically, and there is time to allow the branches to work out their differences in the back and forth of political negotiation and occasional court battles. The president’s attempted encroachment on the constitutional rights of Congress this past Wednesday was anything but metaphorical.