As we await President Trump's prime-time speech on Tuesday night, one open question remains about whether he's going to pitch the possibility of declaring a "national emergency" to justify appropriating the military to build a border wall. I've already explained why I think such an action would be dangerous, but it's also worth taking a moment to consider the politics of such a maneuver.

In a analysis that appeared in the New York Times in which Yale Law Professor Bruce Ackerman mainly focuses on the legal implications of such a move, he notes that under the 1976 National Emergencies Act:



If President Trump declared an emergency, Section Five of the act gives the House of Representatives the right to repudiate it immediately, then pass their resolution to the Senate — which is explicitly required to conduct a floor vote within 15 days.



It would be pretty clear that in such a case, assuming Ackerman's interpretation of the prevailing law is accurate, that the Democratic House would quickly repudiate Trump.

But then, Senate Majority Leader Mitch McConnell would be put in a bind. On the one hand, he wouldn't want to anger Trump's base and be scapegoated for the wall not getting built. On the other hand, there's much less enthusiasm for the wall among the public at large than there is among the base — let alone the idea of using emergency powers. More sober-minded conservative senators would also (hopefully) recognize the potential dangers that such a precedent would set were Trump to go this route. My guess is that McConnell would want to avoid this scenario.