Opinio Juris Symposium: Additional Thoughts on the President’s Military Response Power

Professor Kent’s additional comments helpfully clarify his textual argument on the power to respond to attacks. I now see (I think) that he is relying on a negative implication: the President must not have this power because it would vitiate important powers of Congress. I do think this is a more promising approach than trying to jam the response power into the declare-war clause (which I think is about launching attacks, not about responding to them). But I still don’t see where, specifically, Congress’ power comes from. Congress does have a broad array of military powers, but none seems easily to encompass the military response power (especially if it’s agreed that the declare-war clause does not). Ordering U.S. forces to counterattack against an aggressor is not regulating the armed forces, or raising armies, or issuing letters of marque, or making rules on captures. And to rely on the necessary-and-proper clause, there needs to be a relevant power of Congress (or of another branch) in the first place.

I would say instead that the President has some powers that can be exercised in response to attack, including diplomatic measures (as Professor Kent agrees) and the use of military force (to the extent of forces available). Congress has other powers, most notably the power to provide additional funds and troops to the President (and the powers Professor Kent describes). These are not conflicting but concurrent.

On the President-Obama-in-Pakistan hypothetical, Professors Ku and Kent are right about how I would approach the question. With Pakistan’s consent, this is an easy case (under the historical understanding), because the deployment does not declare war against Pakistan and the war (if there is such a thing) against al-Qaeda is ongoing. Without Pakistan’s consent, I think the result is a little trickier than they suggest, though. We would need to ask whether making an attack in a foreign state against a non-state entity, but not against the foreign state itself, declared war in eighteenth-century terms. As Professor Kent rightly says, exactly when a state of war began in the eighteenth century was often not clear, and I think this may have been true here. Something similar occurred numerous times in the nineteenth and twentieth centuries when the U.S. sent forces across the Mexican border in pursuit of bandits. The most notable case was General Pershing’s pursuit of the revolutionary leader Pancho Villa after the latter’s forces attacked Columbus, New Mexico in 1916. At the time these incursions were not treated as creating a state of war with Mexico, although Mexico vigorously protested. I’m not sure how this would have been treated in the eighteenth century. (As Professor Ku adds, in my model any presidential action would also need to be consistent with international law).

Finally, on the evidence from Washington’s administration: Professor Kent’s quotes all relate to hostilities on the southwest frontier. But Washington, through Secretary Knox, consistently refused to acknowledge the southern governors’ claims that the southwestern Indians had declared war. He was already fighting an unpopular Indian war in the northwest, and hardly wanted another. Whatever the actual situation on the ground (and it seems that the southern governors were exaggerating), as Washington chose to see it there was no war. As a result, the decision to act remained with Congress, and nothing in these quotes or otherwise addresses the President’s power to respond when war is begun by an enemy.