44 Op. O.L.C. __ (Sept. 22, 2020)
12
of international negotiations.” Prohibition of Spending for Engagement of
the Office of Science and Technology Policy with China, 35 Op. O.L.C.
116, 121 (2011) (quotations omitted) (“Engagement of OSTP with Chi-
na”); see also Earth Island Inst. v. Christopher, 6 F.3d 648, 652 (9th Cir.
1993) (“[A] statute’s requirement that the Executive initiate discussions
with foreign nations violates the separation of powers[.]”). It is “impera-
tive” that, “[i]n the conduct of negotiations with foreign governments,”
the “United States speak with one voice,” and the Constitution’s overrid-
ing design is that this “one voice is the President’s.” Issues Raised by
Foreign Relations Authorization Bill, 14 Op. O.L.C. 37, 40 (1990) (quot-
ing Message to the Senate Returning Without Approval the Bill Prohibit-
ing the Export of Technology for the Joint Japan-United States Develop-
ment of FS-X Aircraft (July 31, 1989), 2 Pub. Papers of Pres. George
H.W. Bush 1042, 1043 (July 31, 1989)).
The Constitution also assigns to the President the responsibility to
make treaties. The President has “the sole power to negotiate treaties.”
Zivotofsky, 576 U.S. at 13. The Senate must provide its advice and con-
sent before a treaty may be valid. U.S. Const. art. II, § 2, cl. 2. But even
when the Senate consents, the President still must decide to bring the
treaty into effect by ratifying the treaty. See, e.g., Relevance of Senate
Ratification History to Treaty Interpretation, 11 Op. O.L.C. 28, 32 (1987)
(observing that, even after the Senate provides consent, “the President
may . . . refuse to ratify the treaty”); Restatement (Fourth) of the Foreign
Relations Law of the United States § 303 reporter’s note 5 (Am. Law Inst.
2018) (“Restatement (Fourth)”) (explaining that, after the Senate approves
a treaty, then the ensuing “decision whether to ratify the treaty—and to
take the associated steps to bring the treaty into legal force for the United
States—is vested wholly in the President”). Whether to ratify a treaty is
itself a judgment that falls within the executive power of the President.
The President’s exclusive authority over diplomacy extends not only to
the making of treaties, but to their maintenance as well. The Supreme
Court has long recognized that “the execution of a contract between
nations is to be demanded from, and, in the general, superintended by the
executive of each nation.” Schooner Peggy, 5 U.S. at 109; see also United
States v. The Amistad, 40 U.S. (15 Pet.) 518, 571–72 (1841) (recognizing
that the President’s responsibility to execute the laws “is, if possible,
more imperative” with respect to the execution of treaties than statutes,