Treaty Power and Executive Agreements — Article II and Beyond

The Constitution grants the federal government power to conduct foreign affairs and enter binding international agreements — a power that has been exercised through two distinct mechanisms with very different constitutional foundations. The Treaty Clause of Article II requires the President to seek Senate advice and consent, with two-thirds of Senators present concurring, for a treaty to become law of the United States. This supermajority requirement makes formal treaties politically difficult; since 1945, Presidents have concluded far more international agreements through executive agreements — accords entered into on the basis of prior or subsequent congressional authorization (congressional-executive agreements) or solely on the President's own constitutional authority (sole executive agreements) — without Senate ratification. The constitutional status of executive agreements is contested: they have been used for major international commitments (the Iran nuclear deal, the Paris Climate Agreement, trade agreements), but they are more vulnerable to reversal by subsequent Presidents than formal treaties. Missouri v. Holland (1920) established that treaties can authorize legislation that would otherwise be beyond Congress's enumerated powers — suggesting the Treaty Clause grants the federal government foreign affairs powers beyond the enumerated domestic powers. The interplay between the Treaty Clause, the Supremacy Clause, and the President's constitutional authority in foreign affairs produces a complex body of law governing how the United States enters, modifies, and withdraws from international commitments.

Current Law (2026)

Key Mechanics

The Constitution grants the President power to make treaties with the advice and consent of two-thirds of the Senate (Art. II, § 2, cl. 2), and those treaties are "supreme Law of the Land" under the Supremacy Clause (Art. VI). In practice, the two-thirds Senate requirement is so demanding that Presidents have relied heavily on two alternatives: congressional-executive agreements (approved by simple majority of both Houses — used for USMCA, WTO accession, most trade agreements) and sole executive agreements (based solely on the President's Article II authority — used for the Iran nuclear deal, Paris Agreement, and many bilateral accords). Missouri v. Holland (1920) held that a treaty can authorize Congress to legislate beyond its enumerated domestic powers — treaties open a larger legislative space via the Necessary and Proper Clause. Whether a treaty is self-executing (directly enforceable in court without further legislation) or non-self-executing (requires implementing legislation) turns on treaty text and intent; Medellin v. Texas (2008) held that ICJ judgments under the Vienna Convention are not self-executing and cannot be enforced by presidential directive alone. The Case-Zablocki Act (1 U.S.C. § 112b) requires the President to report all executive agreements to Congress within 60 days — Congress's primary check on executive agreement proliferation. Treaty withdrawal: the Constitution is silent; Goldwater v. Carter (1979) treated the question as a political question, and Presidents have unilaterally withdrawn from treaties (Paris Agreement, Iran JCPOA, INF Treaty) without Senate involvement, though the practice remains constitutionally contested.

Legal Authority

• U.S. Const. art. II, § 2, cl. 2 — "[The President] shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur"
• U.S. Const. art. VI, cl. 2 — Supremacy Clause: "This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land"
• 1 U.S.C. § 112b — Case-Zablocki Act: the President must report all executive agreements to Congress within 60 days; Congress's oversight mechanism for executive agreement proliferation
• 22 U.S.C. § 3301 et seq. — International agreements reporting requirements
• Missouri v. Holland, 252 U.S. 416 (1920) — Federal treaty (migratory bird protection) can authorize legislation under the Necessary and Proper Clause that would not be within Congress's domestic enumerated powers; treaties expand federal legislative capacity
• Dames & Moore v. Regan, 453 U.S. 654 (1981) — President Carter's executive agreement with Iran (settling the hostage crisis, suspending claims) was within the President's power based on long historical practice and implicit congressional acquiescence; Youngstown Category 1/2 analysis
• Medellin v. Texas, 552 U.S. 491 (2008) — ICJ judgment implementing a Vienna Convention treaty obligation is not self-executing; requires implementing legislation; President cannot unilaterally direct states to comply with non-self-executing treaty obligations
• Bond v. United States, 572 U.S. 844 (2014) — Federal criminal statute implementing a chemical weapons treaty did not reach a domestic assault using household chemicals; the Court avoided the Missouri v. Holland issue through statutory interpretation

How It Works

The Treaty Clause: Shared Power and Political Difficulty

The Treaty Clause reflects the Framers' commitment to shared power in foreign affairs. The President negotiates and concludes treaties, but the Senate must approve by a supermajority — a check designed to ensure that major international commitments have broad bipartisan support and that small-state interests (each state has equal Senate representation) are protected.

The two-thirds requirement has made formal treaties politically difficult. Several major international agreements failed Senate ratification: the Versailles Treaty (World War I peace settlement, 1919), the Comprehensive Nuclear Test Ban Treaty (1999), and the Kyoto Protocol (never submitted for ratification) are prominent examples. As the treaty process has become more difficult in a polarized Senate, Presidents have increasingly relied on executive agreements.

Advice and consent: Article II's text calls for the Senate's "advice and consent," suggesting a role before as well as after treaty negotiation. In practice, the Senate's role has been primarily one of consent after the fact — the Senate votes on completed treaty texts rather than providing advice during negotiations. Some Presidents have consulted Senate Foreign Relations Committee members during negotiations; others have not.

Reservations, understandings, and declarations: The Senate often attaches conditions when consenting to a treaty — reservations (conditions that modify the treaty's obligations for the United States), understandings (interpretations of the treaty's meaning), and declarations (political statements). Other parties may reject reservations, potentially preventing ratification.

Treaty supremacy: Under Article VI, treaties are the supreme law of the land — equivalent in status to federal statutes and superior to state law. Treaties made after a federal statute supersede it; federal statutes enacted after a treaty can supersede it as domestic law (even if the United States remains internationally bound). The "last in time" rule applies between treaties and subsequent statutes.

Missouri v. Holland: Treaties and Federal Power

Missouri v. Holland (1920) raised the question of whether Congress could enact the Migratory Bird Treaty Act — implementing a U.S.-Canada treaty protecting migratory birds — even though the Court had previously held that similar federal legislation not based on a treaty exceeded Congress's enumerated domestic powers (particularly the Commerce Clause as then understood). Justice Holmes's opinion for the Court held that the treaty power authorizes legislation that would otherwise exceed Congress's domestic authority:

The constitutional architecture treats treaties as federal obligations distinct from domestic legislative power. When the United States enters a treaty, "there may be matters of the sharpest exigency for the national well-being that an act of Congress could not deal with but that a treaty followed by such an act could." The Necessary and Proper Clause, applied to the treaty power, authorizes Congress to implement valid international obligations.

Missouri v. Holland's expansive reading of the treaty power has been contested. Some scholars and Justices have argued that the treaty power cannot expand federal power beyond constitutional limits — that treaties cannot override other constitutional provisions, including the Tenth Amendment's reservation of powers to states. Bond v. United States (2014) avoided this question through statutory interpretation. The outer limits of Missouri v. Holland remain unresolved.

Executive Agreements: Three Types

The vast majority of international agreements the United States enters are not formal treaties but executive agreements. Three categories have developed:

Congressional-executive agreements: Authorized by prior legislation (congressional pre-authorization) or approved by majority vote of both houses of Congress after negotiation. Major trade agreements — NAFTA (1993), GATT/WTO accession (1994), USMCA (2020) — are congressional-executive agreements. Congress pre-authorized trade negotiations through fast-track/trade promotion authority, committing to an up-or-down vote on completed agreements without amendment. Congressional-executive agreements are placed in Youngstown Category 1 — maximum presidential authority from combination of executive and legislative power.

Executive agreements pursuant to Article II authority: Based on the President's constitutional authority as commander-in-chief, chief executive, and chief diplomat — without congressional authorization. The President's Article II powers support executive agreements to settle international claims (Dames & Moore), establish diplomatic relations, and manage the day-to-day conduct of foreign affairs. These agreements are in Youngstown Category 2 — presidential authority alone — and are the most vulnerable to reversal.

Sole executive agreements at odds with congressional will: If Congress has legislated on a subject and the President enters an executive agreement contrary to that legislation, the agreement may be in Youngstown Category 3 — lowest ebb of presidential power. Courts have generally avoided resolving this conflict directly, finding cases non-justiciable or resolving on other grounds.

Durability and reversal: Formal treaties can only be terminated through the constitutional process (or, controversially, by presidential withdrawal). Executive agreements can be terminated by a subsequent President. This creates significant questions about continuity of international commitments: the Trump administration withdrew from the Paris Climate Agreement (executive agreement), the Iran nuclear deal (JCPOA, executive agreement), and other Obama-era accords. Biden rejoined the Paris Agreement. Trump again withdrew in 2025. This executive agreement carousel illustrates both the flexibility and the fragility of non-treaty international commitments.

Dames & Moore and the Settlement Power

Dames & Moore v. Regan (1981) is the most important case on executive agreements' constitutional validity. After the 1979 Iranian hostage crisis, the Carter administration negotiated the Algiers Accords — executive agreements with Iran settling the hostage situation by, among other things, suspending all pending claims against Iran in U.S. courts and submitting them to an international arbitral tribunal. Dames & Moore challenged this suspension of its $3.5 million claim against Iran.

Justice Rehnquist's unanimous opinion upheld the executive agreement. The Court applied the Youngstown framework:

• For the suspension of claims, Congress had not specifically authorized it but had legislated extensively on international emergency economic powers (IEEPA), creating a framework that evidenced congressional acquiescence in presidential claims settlement power
• Youngstown Category 1 or 2: the President's action was either authorized by statute or was at least acquiesced in by long practice
• The "historical gloss" on the Constitution — a pattern of executive agreements settling claims going back to the Founders — gave the President constitutional authority

Dames & Moore established that presidents can make binding executive agreements on foreign affairs matters without specific congressional authorization, based on historical practice and implied congressional acquiescence.

Treaty Withdrawal: A Constitutional Gap

The Constitution specifies how treaties are made (President + 2/3 Senate) but says nothing about how they are terminated. President Carter's withdrawal from the Mutual Defense Treaty with Taiwan in 1979 was challenged in Goldwater v. Carter, where the Supreme Court dismissed the case as a non-justiciable political question. Since then, Presidents have asserted the power to withdraw from treaties unilaterally — without Senate approval.

President Trump withdrew from the Paris Climate Agreement (2017), INF Treaty (2018), and Open Skies Treaty (2020) without Senate approval. Whether presidential treaty withdrawal requires Senate consent remains a theoretical constitutional question without definitive judicial resolution.

Self-Executing vs. Non-Self-Executing Treaties

Medellin v. Texas (2008) addressed a critical distinction: whether treaties are "self-executing" (directly enforceable in domestic courts without implementing legislation) or "non-self-executing" (requiring Congress to pass implementing legislation before courts can enforce them).

Jose Medellin was a Mexican national on death row in Texas. The International Court of Justice (ICJ) held that the United States had violated the Vienna Convention on Consular Relations by not informing Medellin of his right to contact the Mexican consulate upon arrest. The ICJ ordered review and reconsideration of his sentence. President Bush issued a "Presidential Memorandum" directing Texas courts to comply.

Chief Justice Roberts's majority held that: (1) the ICJ judgment was not self-executing — the Vienna Convention's Optional Protocol did not give the ICJ judgment direct legal force in U.S. courts; and (2) the President's memorandum was insufficient to give the ICJ judgment domestic legal effect. Only Congress could provide implementing legislation. The President cannot unilaterally make non-self-executing treaty obligations enforceable in domestic courts.

How It Affects You

If you are a business operating internationally: Many of the legal frameworks governing your international business — trade rules (WTO, USMCA), investor protections (bilateral investment treaties), intellectual property (Berne Convention, TRIPS), financial regulation (Basel accords implemented through statute), and more — are based on treaty obligations or executive agreements. These agreements create rights you can sometimes enforce in domestic courts (if self-executing) or through international arbitration. When executive agreements are revoked by subsequent Presidents, your treaty-based protections may become uncertain — plan international contracts and investments with awareness of the political durability of the underlying agreement. The status of specific bilateral investment treaties, tax treaties, and WTO obligations has fluctuated with changing administrations.

If you are a foreign national in the United States: Several treaty obligations affect your rights. The Vienna Convention on Consular Relations (Medellin) gives you the right to contact your country's consulate if arrested. Tax treaties between the United States and your country may reduce or eliminate double taxation of income. Bilateral agreements govern the mutual recognition of professional credentials. Treaty rights are only as enforceable in U.S. courts as their self-executing status permits — many require you to assert rights through consular or diplomatic channels rather than domestic courts.

If you are a President or executive branch foreign policy official: The treaty process is extremely slow and politically uncertain — the 2/3 Senate vote may be impossible for controversial agreements. For major multilateral commitments, congressional-executive agreements (majority votes in both houses) are more achievable. For executive agreements on matters within your Article II authority, you can act without congressional approval — but those agreements will be vulnerable to reversal by your successor. Consider whether durability and credibility require Senate ratification rather than executive action; short-term flexibility may come at the cost of long-term reliability. Case-Zablocki Act reporting requirements apply to all executive agreements — report them within 60 days.

If you are a Senator or congressional staffer: The Senate's 2/3 advice and consent power over treaties is one of the chamber's most significant constitutional prerogatives. Asserting this prerogative requires political will — when Presidents circumvent it with executive agreements, the Senate can respond through legislation (conditioning funding, enacting competing rules, requiring Senate approval for specific categories of agreements) or through political pressure. The Case-Zablocki Act's reporting requirements give Congress a window into executive agreements; the Senate Foreign Relations Committee's oversight role provides institutional capacity to monitor and respond to major executive agreements that circumvent the treaty process.

State Variations

Treaties are federal law supreme over conflicting state law under the Supremacy Clause. States cannot enter treaties — Article I, Section 10 explicitly prohibits states from entering "any Treaty, Alliance, or Confederation." Several state dimensions remain:

State law preemption by treaties: Under the Supremacy Clause, valid self-executing treaties preempt inconsistent state laws. A treaty provision directly conflicting with a state law prevails. Zschernig v. Miller (1968): Oregon probate law that conditioned inheritance by East German citizens on reciprocity was preempted by federal foreign affairs power, even absent a specific treaty provision.

State implementation of non-self-executing treaties: When Congress enacts implementing legislation for non-self-executing treaties, state law must comply with that legislation (like any federal statute). States may need to modify their own laws to comply with implementing legislation.

State sovereign immunity: Federal courts cannot use treaties to compel states to waive sovereign immunity without their consent (Eleventh Amendment). This has been an issue in cases where states were named as parties in treaty-based disputes.

JCPOA and Iran sanctions: Multiple states have enacted their own Iran sanctions laws affecting public pension fund investments; some conflict with federal executive policy. This illustrates the tension between state foreign policy initiatives and the federal government's exclusive treaty power.

Pending Legislation

• Trade Promotion Authority (TPA): Legislation periodically renewed to give the President fast-track authority to negotiate trade agreements that Congress will vote on without amendment; expired in 2021 and renewal has been debated.
• Treaty implementation legislation: Specific implementing legislation pending for various U.S. treaty obligations in areas including climate (Paris Agreement), law of the sea (UNCLOS — the United States has not ratified), and international criminal law.
• Senate treaty reform: Periodically proposed amendments to the Senate's treaty process — including requiring faster action, limiting procedural delays, or changing the supermajority threshold — have not been enacted.

Recent Developments

• 2019 — Trump INF Treaty withdrawal: United States withdrew from the 1987 Intermediate-Range Nuclear Forces Treaty with the Soviet Union (a Senate-ratified treaty), citing Russian violations — withdrawal effected by presidential notice without Senate action, continuing the pattern of unilateral presidential treaty termination since Goldwater v. Carter.
• 2020 — USMCA ratification: United States-Mexico-Canada Agreement ratified as a congressional-executive agreement; replaced NAFTA.
• 2021 — Biden Paris Climate Agreement rejoining: Biden rejoined the Paris Agreement on his first day in office by executive agreement; illustrates the reversibility of executive agreements.
• 2022 — CHIPS Act and international semiconductor agreements: Trade and investment agreements related to semiconductor supply chains negotiated outside the formal treaty process; illustrates the role of executive agreements in modern technology policy.
• 2025 — Trump Paris Agreement withdrawal (again): Within days of taking office, Trump again withdrew from the Paris Climate Agreement; illustrated the executive agreement's vulnerability to reversal.
• 2025–2026 — WHO and international health agreements: Trump administration's withdrawal from the World Health Organization and renegotiation of international health cooperation agreements raised questions about the scope of presidential authority to exit multilateral treaty organizations.