At Lawfare , Matthew Waxman notes The Anniversary of the Monroe Doctrine (announced December 2, 1823) and questions its constitutionality:

Monroe’s proclamation is a momentous example of the president’s vast constitutional power to set and communicate U.S. foreign policy. This was not just any kind of diplomatic policy, however.

This was drawing a red line—with an implicit war threat—even though the United States at the time lacked the military power to back it up. The United States was counting on Britain, which too wanted to keep continental European powers out of Latin America, to also intervene if necessary. “In its sweep and bravado,” writes Kori Schake in “Safe Passage: The Transition from British to American Hegemony,” “the Monroe Doctrine has few equals, especially since it was promulgated by a country that was not the peer of the states—Britain, France, and Spain—whose activity it sought to curtail.” …

The late legal historian David Currie noted in his volumes on the Constitution in Congress that “[v]irtually no one questioned [Monroe’s proclamation] at the time. Yet it posed a constitutional difficulty of the first importance.” The president was unilaterally committing the nation to war if European states crossed Monroe’s red lines, but it was Congress’s sole prerogative to initiate war. By putting U.S. prestige and credibility on the line, his threat limited Congress’s practical freedom of action if European powers chose to intervene. When he succeeded Monroe as president, Adams faced complaints from opposition members of Congress that Monroe’s proclamation had exceeded his constitutional authority and had usurped Congress’s power by committing the United States—even in a nonbinding way—to resisting European meddling in the hemisphere.

I don’t see the problem with the Monroe Doctrine as its infringement on Congress’ war powers.  Congress remained free not to back up the proclamation if European powers violated it.  It was, in reverse, akin to the earlier Neutrality Proclamation issued by President Washington in 1793, which announced that the U.S. would not  go to war against Britain or France.  Madison and others argued that this proclamation infringed Congress’ war powers by committing the United States not to go to war even if Congress wanted to.

But Hamilton, in his Pacificus essays, gave the persuasive response: the Proclamation didn’t prevent Congress from declaring war if it wanted to.  And in modern practice the Senate approves treaties that commit the U.S. to go to war if an ally is attacked.  These are similar to the Monroe Doctrine in that they promise something (a declaration of war) that the promisors can’t deliver — and more worryingly, they make a binding promise under international law.  But still, Congress can refuse to follow through, so they do not unconstitutionally constrain Congress.

The bigger difficulty for the Monroe Doctrine (and the Neutrality Proclamation) is where the President gets the constitutional power to declare them in the first place.  None of the specific powers in Article II, Sections 2 and 3, seems apposite.  The closest are probably the powers to send and receive ambassadors, but the first of these is actually a shared power of the Senate, and in any event neither the Doctrine nor the Proclamation was delivered to or through ambassadors.

My answer, sketched in an article from a while back with Professor Saikrishna Prakash, is the the power comes from the vesting clause of Article II, Section 1.  Diplomatic power — the power to announce U.S. foreign policy to other nations — historically was an executive power, and thus is incorporated into this grant of power along with the power to execute the laws.  (This was also Hamilton’s answer to the same question regarding the Neutrality Proclamation, which makes me somewhat more confident about it).

This answer is not accepted by all — but for those who don’t accept it, I’m unclear how they can find the diplomatic power in the Constitution’s original meaning.

NOTEThis post was originally published at The Originalism Blog, “The Blog of the Center for the Study of Constitutional Originalism at the University of San Diego School of Law,” and is reposted here with permission from the author.

Michael D. Ramsey
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