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Treaties: A Historical Overview

Chapter 1: The Senate's Role in Treaties
Chapter 2: Historical Development
Chapter 3: Process
Chapter 4: Rejected Treaties

The Senate's Role in Treaties

The Constitution 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" (Article II, section 2). The Constitution's framers gave the Senate a share of the treaty power in order to give the president the benefit of the Senate's advice and counsel, check presidential power, and safeguard the sovereignty of the states by giving each state an equal vote in the treaty-making process. As Alexander Hamilton explained in The Federalist, No. 75, "The operation of treaties as laws, plead strongly for the participation of the whole or a portion of the legislative body in the office of making them." The constitutional requirement that the Senate approve a treaty with a two-thirds vote means that successful treaties must gain support that overcomes partisan division. The two-thirds requirement adds to the burdens of the Senate leadership and may also encourage opponents of a treaty to engage in a variety of dilatory tactics in hopes of obtaining sufficient votes to ensure its defeat.

The Senate does not ratify treaties—the Senate approves or rejects a resolution of ratification. If the resolution passes, then ratification takes place when the instruments of ratification are formally exchanged between the United States and the foreign power(s).

Most treaties submitted to the Senate have received the Senate's advice and consent to ratification. During its first 200 years, the Senate approved more than 1,500 treaties and rejected only 21. A number of these, including the Treaty of Versailles, were rejected twice. Most often, the Senate has simply not voted on treaties that its leadership deemed not to have sufficient support within the Senate for approval, and in general these treaties have eventually been withdrawn. At least 85 treaties were eventually withdrawn because the Senate never took final action on them. Treaties may also remain in the Senate Foreign Relations Committee for extended periods, since treaties are not required to be resubmitted at the beginning of each new Congress. There have been instances in which treaties have lain dormant within the committee for years, even decades, without action being taken.

Historical Development

During the summer of 1787, delegates to the Constitutional Convention debated the structure and responsibilities of a new legislative body. One of the questions they posed was, should the power of treaty making reside within the legislative or executive branch? Under the Articles of Confederation a treaty could be entered into with the consent of nine of the thirteen states, or two-thirds. Some delegates, such as South Carolina's Charles Pinckney, urged that the Senate, where each state had equal representation, should have the sole power to make treaties. Alexander Hamilton argued that the executive branch should exercise powers related to foreign relations and should therefore have the power to make treaties "with the advice and approbation of the Senate." In the end, Hamilton's argument proved the most persuasive.

Since the First Congress convened on March 4, 1789, the U.S. Senate has carefully guarded its concurrent power in treaty making. On August 22, 1789, President George Washington and Secretary of War Henry Knox arrived at the Senate Chamber seeking the Senate's advice and consent to a treaty with Native American tribes. While the president, seated in the presiding officer's chair, and his secretary waited, the Senate voted to refer these questions to a committee rather than debate the issue in the presence of the august president. Irritated, Washington decided that, in the future, he would send communications regarding treaties in writing, setting the precedent that all of his successors have followed.

The Senate approved the ratification of one of the most contentious treaties in U.S. history during the Washington administration. At the urging of Federalist Party senators, the president sent Chief Justice John Jay to London to settle open disputes with Great Britain. Washington did not consult the full Senate before requesting its advice and consent to the completed treaty, known as the Jay Treaty. The treaty's opponents, mostly Jeffersonian Republicans, supported New York senator Aaron Burr's motion to reopen the negotiations, pursuant to a set of specific proposals, but Federalist senators defeated that plan and secured the approval of the controversial Jay Treaty on June 24, 1795. Jeffersonian Republicans in control of the House of Representatives threatened to withhold the funding necessary to effect some of its provisions, but the appropriation ultimately passed the House on April 30, 1796, by a narrow margin. It was a critical victory for the Senate's unique and vital role in the making of treaties.

Originally, the Senate had conducted its sessions behind closed doors, and debates over the Jay Treaty were no exception. Even after the Senate opened a public gallery in December 1795, the tradition of debating treaties and nominations in secret session continued into the early 20th century. Newspapers frequently published accounts of the secret discussions, occasionally printing the text of a treaty before senators received their official copies. The Senate investigated, fretted, and protested but proved powerless to stop the leaks, which likely came from the members themselves. Not until 1929 were executive sessions routinely open to the press and the public. Today the Senate holds closed sessions only under the rarest of circumstances, usually to deal with classified information.

Advice and Consent

The Constitution provides that the Senate exercise its "advice and consent" in treaty making, an ambiguous phrase that presidents and senators have debated since the nation's founding. During the War of 1812, Delaware senator James Bayard was a member of the delegation to negotiate the Treaty of Ghent. His presence raised the question of whether having senators on the negotiating team would make the Senate more favorably inclined to approve the treaty, or whether it would violate the separation of powers. That debate has continued for generations without resolution.

The Senate rejected a number of treaties during the last quarter of the 19th century. In an effort to avoid the same fate for his peace treaty with Spain, President William McKinley shrewdly named three U.S. senators to negotiate the treaty in 1898. Senators from both parties roundly criticized his action, but the Senate ultimately approved ratification of the resulting treaty. A generation later, senators criticized President Woodrow Wilson for not including members in the delegation that negotiated the Treaty of Versailles, ending World War I and establishing the League of Nations. Instead, Wilson personally negotiated the treaty. When the president hand delivered the treaty to the Senate on July 10, 1919, most Democrats supported it, but Republicans were divided. The "Reservationists," led by Senator Henry Cabot Lodge, called for approval of the treaty only if certain reservations, or alterations, were adopted. The "Irreconcilables" opposed the treaty in any form. In November Lodge sent the treaty with 14 reservations to the Senate floor, prompting an angry Wilson to urge Democrats to reject Lodge's plan. On November 19, 1919, a group of Democratic senators joined the Irreconcilables to defeat the treaty. The United States never ratified the Treaty of Versailles, nor did it join the League of Nations.

With the Treaty of Versailles in mind, Wilson's successor, Warren G. Harding—who had served as a senator during the fight for the treaty's ratification—appointed Senator Lodge and Democratic Leader Oscar Underwood as delegates to the Washington Arms Limitation Conference to improve the likelihood of the Senate's consent to ratification. For much the same reason, Presidents Franklin Roosevelt and Harry Truman involved the chairman, Tom Connally, and the ranking Republican of the Senate Foreign Relations Committee, Arthur Vandenberg, in the creation of the United Nations. This action helped to spare the UN the fate of the League of Nations; there were only two Senate votes against its charter.

Executive Agreements

In addition to treaties, which may not enter into force and become binding on the United States without the advice and consent of the Senate, there are other types of international agreements concluded by the executive branch and not submitted to the Senate. These are classified in the United States as executive agreements, not as treaties, a distinction that has only domestic significance. International law regards each mode of international agreement as binding, whatever its designation under domestic law.

The challenge of obtaining a two-thirds vote on treaties was one of the motivating forces behind the vast increase in executive agreements after World War II. In 1952, for instance, the United States signed 14 treaties and 291 executive agreements. This was a larger number of executive agreements than had been reached during the entire century of 1789 to 1889. Executive agreements continue to grow at a rapid rate.

In recent years, the growth in executive agreements is also attributable to the sheer volume of business conducted between the United States and other countries, coupled with the already heavy workload of the Senate. Many international agreements are of relatively minor importance and would needlessly overburden the Senate if they were submitted as treaties for advice and consent. Another factor has been the passage of legislation authorizing the executive branch to conclude international agreements in certain fields, such as foreign aid, agriculture, and trade. Treaties have also been approved that authorize further agreements between the parties. According to a 1984 study by the Senate Committee on Foreign Relations, "88.3 percent of international agreements reached between 1946 and 1972 were based at least partly on statutory authority; 6.2 percent were treaties, and 5.5 percent were based solely on executive authority."

Terminating Treaties

The Constitution is silent about how treaties might be terminated. The breaking off of two treaties during the Jimmy Carter administration stirred controversy. In 1978 the president terminated the U.S. defense treaty with Taiwan in order to facilitate the establishment of diplomatic relations with the People's Republic of China. Also in 1978 the new Panama Canal treaties replaced three previous treaties with Panama. In one case, the president acted unilaterally; in the second, he terminated treaties in accordance with actions taken by Congress. Only once has Congress terminated a treaty by a joint resolution; that was a mutual defense treaty with France, from which, in 1798, Congress declared the United States "freed and exonerated." In that case, breaking the treaty almost amounted to an act of war; indeed, two days later Congress authorized hostilities against France, which were only narrowly averted


When a treaty is submitted to the Senate for approval, the Senate has several options for action. The Senate may approve or reject the treaty as it has been submitted or it may make its approval conditional by including in the resolution amendments to the text of the treaty—reservations, understandings, interpretations, declarations, or other statements. The president and the other countries involved must then decide whether to accept the conditions and changes in the legislation, renegotiate the provisions, or abandon the treaty. Finally, the Senate may choose to take no definitive action, leaving the treaty pending in the Senate until withdrawn at the request of the president or, occasionally, at the initiative of the Senate.

For additional information about the role of the Senate in the making of treaties and other international agreements, download the study, Treaties and Other International Agreements: The Role of the United States Senate prepared by the nonpartisan Congressional Research Service for the Senate Committee on Foreign Relations.

Rejected Treaties
DateTreaty-making CountrySubjectVote
1825_0309 Mar 9, 1825 Colombia Suppression of African Slave Trade Yeas=0; Nays=40
1836_0611 Jun 11, 1836 Switzerland Personal and property rights Yeas=14; Nays=23
1844_0608 Jun 8, 1844 Texas Annexation Yeas=16; Nays=35
1844_0615 Jun 15, 1844 German Zollverein Reciprocity Yeas=26; Nays=18
1860_0531 May 31, 1860 Mexico Transit and commercial rights Yeas=18; Nays=27
1860_0627 Jun 27, 1860 Spain Cuban Claims Commission First vote: Yeas=25; Nays=17
Second vote: Yeas=24; Nays=18
1869_0413 Apr 13, 1869 Great Britain Arbitration of claims Yeas=1; Nays=54
1870_0601 Jun 1, 1870 Hawaii Reciprocity Yeas=20; Nays=19
1870_0630 Jun 30, 1870 Dominican Republic Annexation Yeas=28; Nays=28
1883_0115 Jan 15, 1883;
1886_0420 Apr 20, 1886
Mexico Mining claims 1883_0115 Jan 15, 1883: Yeas=33; Nays=20
1886_0420 Apr 20, 1886: Yeas=32; Nays-26
1885_0129 Jan 29, 1885 Nicaragua Interoceanic canal Yeas=32; Nays=23
1888_0821 Aug 21, 1888 Great Britain Fishing rights Yeas=27; Nays=30
1889_0201 Feb 1,1889 Great Britain Extradition Yeas=15; Nays=38
1897_0505 May 5, 1897 Great Britain Arbitration Yeas=43; Nays=26
1919_1119 Nov 19, 1919;
1920_0319 Mar 19, 1920
Multilateral Treaty of Versailles 1919_1119 Nov 19,1919: Yeas=38; Nays=53
1920_0319 Mar 19, 1920: Yeas=49; Nays=35
1927_0118 Jan 18, 1927 Turkey Commercial rights Yeas=50; Nays=34
1934_0314 Mar 14, 1934 Canada St. Lawrence Seaway Yeas=46; Nays=42
1935_0129 Jan 29, 1935 Multilateral World Court Yeas=52; Nays=36
1960_0326 May 26, 19601 Multilateral Law of the Sea Convention Yeas=29; Nays=30
1983_0308 Mar 8, 19832 Multilateral Montreal Aviation Protocols Yeas=50; Nays=42
1999_0813 Oct 13, 1999 Multilateral Comprehensive Nuclear Test Ban Treaty Yeas=48; Nays=51
2012_1204 Dec 4, 2012 Multilateral Convention on the Rights of Persons with Disabilities Yeas=61; Nays=38

1 Approved on May 26, 1960, with vote of 77 to 4; vote immediately followed by motion to reconsider, and on second vote treaty was rejected 49 to 30; second motion to reconsider was introduced on May 27, 1960, but was not taken up; treaty remained on calendar of Committee on Foreign Relations until 2000, when it was returned to the president.

2 Rejected on March 8, 1983, with vote of 50 to 42; motion to reconsider was entered but not taken up; treaty remained on calendar of Committee on Foreign Relations until 1998, when it was returned to the president as part of the resolution of ratification for Montreal Protocol No. 4.

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