Treaty Power — International Agreements & Senate Ratification

The Treaty Clause (Article II, Section 2, Clause 2) provides that 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." Treaties are the formal mechanism by which the United States enters into binding international agreements — from NATO and the UN Charter to arms control treaties, trade agreements, tax treaties, and human rights conventions. Once ratified by a two-thirds Senate vote, a treaty becomes the "supreme Law of the Land" under the Supremacy Clause (Article VI) — on par with federal statutes, and can preempt state law. But in practice, the treaty power is far more complex than this suggests. The two-thirds threshold makes Senate ratification extremely difficult — and presidents have increasingly turned to executive agreements (agreements made by the President without Senate treaty ratification) to conduct foreign affairs. Executive agreements outnumber treaties by roughly 10 to 1. They come in three forms: congressional-executive agreements (authorized or approved by a simple majority of both houses — like trade agreements under Trade Promotion Authority), sole executive agreements (made under the President's independent constitutional authority — like diplomatic recognition), and executive agreements pursuant to treaties (implementing existing treaty obligations). The Supreme Court in Medellin v. Texas (2008) held that not all treaties are self-executing — a non-self-executing treaty requires implementing legislation before it creates domestically enforceable law. This distinction determines whether individuals can invoke treaty provisions in U.S. courts.

Current Law (2026)

Legal Authority

• U.S. Constitution, Art. II, § 2, cl. 2 — "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. Constitution, Art. VI, cl. 2 — Treaties are the "supreme Law of the Land"
• Missouri v. Holland (1920) — Treaty power is not limited by the Tenth Amendment; Congress may legislate to implement treaties even beyond its other enumerated powers
• Medellin v. Texas (2008) — Non-self-executing treaties do not create judicially enforceable domestic law without implementing legislation; the President cannot unilaterally make a non-self-executing treaty enforceable
• Bond v. United States (2014) — Narrowly construed the Chemical Weapons Convention Implementation Act; even treaty-implementing legislation is subject to ordinary principles of statutory interpretation

How It Works

The President negotiates and signs treaties, but they do not become binding until the Senate gives "advice and consent" by a two-thirds vote. The Senate Foreign Relations Committee holds hearings and recommends approval — often with conditions, reservations, understandings, and declarations ("RUDs") that modify U.S. obligations. The two-thirds threshold ensures broad bipartisan support for international commitments and is intentionally hard to clear; the U.S. has signed but never ratified the Convention on the Rights of the Child, the Convention on the Elimination of All Forms of Discrimination Against Women, and the Rome Statute of the International Criminal Court, among others. Whether a ratified treaty can be enforced in U.S. courts depends on whether it's self-executing or non-self-executing — a distinction clarified in Medellin v. Texas (2008). A self-executing treaty creates judicially enforceable rights immediately upon ratification; a non-self-executing treaty expresses an international commitment but requires implementing legislation before it has domestic legal force. In Medellin, the Court held that the ICJ's judgment (under the Vienna Convention on Consular Relations) was not directly enforceable — and the President couldn't unilaterally make it so through executive memorandum.

Because the two-thirds threshold is so difficult, presidents increasingly use executive agreements instead. Congressional-executive agreements are approved by simple majority of both chambers — NAFTA, the WTO agreements, and most modern trade deals used this route under Trade Promotion Authority. Sole executive agreements are made on the President's independent constitutional authority (Commander-in-Chief, diplomatic recognition) with no congressional role, covering military base agreements, intelligence-sharing protocols, and diplomatic arrangements. Treaty-based executive agreements implement obligations under existing ratified treaties. The constitutional line between treaties requiring a Senate supermajority and executive agreements requiring less (or nothing) remains blurry, and the trend toward executive agreements has measurably shifted foreign affairs power from the Senate to the presidency. Treaty termination is equally murky: the Constitution specifies how treaties are made but not unmade. In Goldwater v. Carter (1979), the Court dismissed a challenge to President Carter's unilateral termination of the Taiwan mutual defense treaty without reaching the merits; presidents have since terminated treaties unilaterally — including Trump's withdrawal from the INF Treaty, Paris Climate Agreement, and Iran nuclear deal — and Congress has not successfully challenged these actions in court.

How It Affects You

If you live or work internationally: Treaties shape more of your daily financial life than most people realize. Tax treaties — the U.S. has bilateral income tax treaties with 68 countries — determine how your foreign-source income is taxed. Without a tax treaty, income earned in or paid from a foreign country may be taxed both there and in the U.S. at full rates; tax treaties typically reduce or eliminate withholding taxes on dividends, interest, and royalties, and provide tie-breaker rules for residents of both countries. Look up the U.S. treaty network at irs.gov/businesses/international-businesses/united-states-income-tax-treaties-a-to-z. Totalization agreements — a separate category of Social Security treaties — prevent dual Social Security taxation when you work in a treaty country; the U.S. has totalization agreements with 30 countries, reducing the combined payroll tax burden for internationally mobile workers. If you're working abroad and your employer is paying local social contributions, check ssa.gov/international/agreements_overview.html to see if a totalization agreement applies.

If you're a business with international operations: Three treaty categories directly affect your legal and financial exposure. Bilateral Investment Treaties (BITs) — the U.S. has BITs with 40+ countries — protect U.S. investors from expropriation without compensation and give you access to investor-state arbitration (often through ICSID) if a host government takes action that impairs your investment. Trade agreements (USMCA, bilateral FTAs with 20 countries) set tariff schedules and rules of origin that determine what you pay to import. Mutual Legal Assistance Treaties (MLATs) govern how foreign governments obtain U.S. company records in criminal investigations — relevant if you operate in countries that may seek to compel evidence held in the U.S. Find all active U.S. trade agreements at ustr.gov/trade-agreements.

If you're a foreign national arrested in the United States: The Vienna Convention on Consular Relations — to which the U.S. is a party — gives you the right to contact your country's consulate when you are arrested or detained. U.S. law enforcement is required to inform you of this right without delay. This right exists regardless of your immigration status. Under the Medellin line of cases, the consular notification right is technically in the treaty, but enforcement in domestic courts has been inconsistent — state courts don't always observe the remedy of suppression or vacatur for violations. Ask immediately: "I want to contact my consulate." Your consulate can help you find legal representation, monitor conditions of detention, and in some cases advocate with prosecutors. Contact your consulate directly or use embassies.com to find your country's consular contact in the U.S.

If you follow foreign policy and constitutional law: The treaty power's practical operation in the 21st century is dominated by a structural tension: the formal Article II treaty process requires a two-thirds Senate vote that is almost impossible to achieve for controversial international commitments, so presidents use executive agreements instead. The result is that major international commitments — the Iran nuclear deal (JCPOA), the Paris Climate Agreement, the Trans-Pacific Partnership — are structured as executive agreements that can be entered and exited unilaterally by presidents without congressional input. This is legally defensible but constitutionally awkward: the Founders specifically chose a supermajority treaty threshold to prevent hasty international entanglements, but that threshold now makes treaty-based commitments nearly impossible and concentrates foreign affairs power in the executive branch. Whether a future Congress will reclaim treaty power through legislation requiring Senate involvement in major agreements — or whether the executive agreement equilibrium becomes permanent — is one of the open structural questions in U.S. constitutional governance.

State Variations

Treaties preempt state law under the Supremacy Clause:

• Missouri v. Holland (1920) established that the treaty power can reach subjects beyond Congress's other enumerated powers — potentially allowing treaty implementation to override state authority in areas otherwise reserved to states under the Tenth Amendment
• State courts must apply self-executing treaties as the "supreme Law of the Land"
• States cannot conduct their own foreign policy or enter into treaties (Article I, § 10 — "No State shall enter into any Treaty")
• State laws that conflict with treaty obligations are preempted

Implementing Regulations

This is a constitutional provision with no implementing regulations in the Code of Federal Regulations. Key judicial doctrine includes:

• Missouri v. Holland (1920) — Treaty power is broader than Congress's other enumerated powers; Congress may legislate to implement a treaty even if the subject matter would otherwise be reserved to the states under the Tenth Amendment
• Reid v. Covert (1957) — Treaties cannot override constitutional rights; the Constitution places limits on what the treaty power can accomplish, and no international agreement can strip Americans of their Bill of Rights protections
• Goldwater v. Carter (1979) — Treaty termination by the President without Senate consent was dismissed as a political question; the Court issued no majority opinion on the merits, leaving presidential unilateral withdrawal largely unresolved
• Medellin v. Texas (2008) — Non-self-executing treaties do not create judicially enforceable domestic law without implementing legislation; the President cannot unilaterally transform a non-self-executing treaty obligation into binding domestic law
• Bond v. United States (2014) — Courts apply ordinary principles of statutory construction to treaty-implementing legislation; Congress is presumed not to use the treaty power to alter the usual constitutional balance between federal and state authority without clear statement

Pending Legislation

No standalone constitutional amendment legislation pending in the 119th Congress. See Arms Control & Weapons Treaties for treaty ratification activity, and Separation of Powers for related legislative activity in this area.

Recent Developments

Treaty power disputes have centered on executive agreement practice and unilateral withdrawal. The Iran nuclear deal (JCPOA, 2015) was structured as an executive agreement rather than a treaty — allowing President Trump to withdraw unilaterally in 2018 without Senate involvement. The Paris Climate Agreement was similarly structured. These high-profile uses of executive agreements have renewed debate about whether significant international commitments should be submitted as treaties requiring Senate supermajority approval. Bond v. United States (2014) introduced a potential federalism limit on the treaty power — the Court construed a treaty-implementing statute narrowly to avoid raising questions about whether the treaty power allows Congress to override traditional state authority without limit. In February 2026, the Trump administration issued an executive action addressing U.S. withdrawal from an international agreement, continuing the administration's pattern of reassessing multilateral commitments through unilateral executive action.