Rep. Joaquin Castro (D-Tex.) speaks last month about the resolution he sponsored to terminate President Trump's emergency declaration. (Chip Somodevilla/Getty Images)

Danielle Allen is a political theorist at Harvard University and a contributing columnist for The Post.

Some media have been calling the resolution passed in Congress to block President Trump’s declaration of a national emergency at the border a “resolution of disapproval.” It is not. It is, instead, a “resolution of termination.” The 1976 National Emergencies Act gives the president the power to declare emergencies. It also gives Congress the power to terminate them. Congress has never sought to use this power before. It’s good that it is doing so now.

Rep. Joaquin Castro (D-Tex.), the principal sponsor of the resolution, is relying on this provision in the 1976 law: Sec. 202 (a): “Any national emergency declared by the President in accordance with this title shall terminate if — (1) Congress terminates the emergency by concurrent resolution.” In other words, Congress of the 1970s did not intend to give the president a blank check. Even as it delegated power, it sought to retain some for itself.

That power, however, was substantially weakened by a subsequent Supreme Court decision, in an unrelated area, that made this termination resolution subject to presidential veto. As Congress designed the emergencies act, it could stop a president via simple majority vote in both houses. Now, however, the president must sign any such resolution of termination and, therefore, also can veto it. Congress has the power to overrule the president only in conditions where our representatives can achieve a supermajority vote of two-thirds.

Fortunately, for all of its tepid defense of its own powers over the past few decades, Congress is now looking around — shaking its power piggy bank — to try to find where it has left its authority. This is a very good thing. The great discovery of the 18th-century Age of Revolution is that separating legislative power from executive power, and putting legislative power in the hands of the people’s representatives, open up space for freedom by substantially reducing the likelihood that any citizen will suffer under arbitrary and unconstrained exercises of power. While political philosophy would have to travel many leagues beyond this point to recognize the importance of protecting the full range of humanity, this discovery of how to organize the powers of government was fundamental, transformative and good.

The House vote checking Trump has been reported as a resolution of disapproval out of confusion with another mechanism that Congress has developed to try to claw back power from the executive.

The 1996 Contract with America Advancement Act included a subtitle known as the Congressional Review Act, which gave Congress the authority to nullify, via a “resolution of disapproval,” any regulation passed by a federal agency. In other words, Congress gave itself the power of “after-the-fact” legislation. Having delegated great power to the executive branch, and having fueled the growth of the administrative and regulatory state, Congress — here led by the Republicans — sought to walk back that delegation. Although this provision was scarcely used after its passage, the Republican-majority Congress that came in with Trump in 2016 quickly secured passage of 14 such “resolutions of disapproval” to roll back Obama-era regulations. Trump signed all of them.

Now, the Democrats, too, are exploring the idea that fundamental democratic principles may be at stake in the face of executive overreach. If these explorations deepen and extend, we will have some small basis for cross-partisan collaboration in restoring the foundations of our political home. Congress is the only branch in which almost all of us feel represented to some degree, regardless of which party is in the majority. Consequently, if we can rebuild the power of the legislative branch, we will restore the integrity of representation and the legitimacy of our political institutions.

The authors of (most of) the Federalist Papers, James Madison and Alexander Hamilton, believed that when the various clever mechanisms they had designed to generate a separation of powers and checks and balances began to fail, there would always be one final line of defense: the people as represented in the House in particular. Writing in Federalist No. 63, one of them — and we don’t know which one — contemplated possible abuses of power by the Senate and wrote that “if such a revolution should ever happen from causes which the foresight of man cannot guard against, the House of Representatives, with the people on their side, will at all times be able to bring back the Constitution to its primitive form and principles.”

The House has done its job — with both parties contributing. We can stand up and cheer. If the Senate does its job, we will cheer even louder. And if our two houses can both shake those power piggy banks and turn out a supermajority to reclaim power for the legislative branch, we will vociferously celebrate a restoration of legitimacy to our political institutions.