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The diplomatic history of the United States oscillated among three positions: isolation from diplomatic entanglements (but with economic connections to the world); alliances with European and other military partners; and unilateralism, or becoming entangled in the world but operating on its own decisions.
1778 - Treaty of Alliance (1778). France and US agreed to come to each others aid in event of British attack from the present time and forever, abrogated in late 1799 after XYZ Affair.
1795 - Treaty of Madrid (1795) established boundaries with the Spanish colonies of Florida and Louisiana and guaranteed navigation rights on the Mississippi River.
1796 - Treaty of Tripoli; Peace treaty between the United States and the Barbary State of Tripoli. Notable for the confirmation by the U.S. that the American government was non-religious in origin and practice. Violated in 1801 by the Basha of Tripoli which led to the Tripolitanian War.
1819 - Adams-Onis Treaty: Spain ceded Florida to US for US$5,000,000 (after Florida was invaded by Andrew Jackson with unclear approval of President Monroe on the pretense of suppressing Seminole Indian raids), US agreed to assume claims against Spain, US gave up claims to Texas.
1823 - Monroe Doctrine. British Foreign Minister Canning proposed US join England in stating that European powers not be permitted further American colonization. Monroe states on December 2 as independent American Policy.
1833 - Argentina. A naval force was sent to attack the Falklands Islands, at the time under Argentine control, in retaliation for the seizing of US ships fishing in Argentine waters. Puerto Soledad settlement virtually destroyed.
1835-36 - Peru. Marines protected American interests in Callao and Lima during an attempted revolution.
1837 - Caroline Affair; A band of Canadian rebels took refuge on Navy island on Canadian side Niagara River, US sympathizers supplied them with aid via steamboat Caroline. On December 29, Canadian forces crossed to US and set Caroline ablaze. May 29, 1838 US forces burned British steamer Sir Robert Peel while in US.
1838 - Aroostook War. Disagreement over Northern Boundary of Maine resulted in troops being called on both sides, Martin Van Buren arranged truce while a commission was established.
1850 - Clayton-Bulwer Treaty. US and Britain agreed that both nations were not to colonize or control any Central American republic, neither nation would seek exclusive control of Isthmian canal, if canal built protected by both nations for neutrality and security. Any canal built open to all nations on equal terms.
1852-53 - Argentina; February 3 to 12, 1852; September 17, 1852 to April 1853. Marines were landed and maintained in Buenos Aires to protect American interests during a revolution.
1853 - Gadsden Purchase: Purchase of 30,000 square miles (78,700 km²) south of Gila River for US$10,000,000 for purpose of Railroad line pass through Rockies.
1853 - Nicaragua; March 11 to 13. U.S. forces landed to protect American lives and interests during political disturbances.
1854 - Kanagawa Treaty; Millard Fillmore sent Matthew Perry to Tokyo, he arrived in 1853 and delivered a letter, returning next year with seven warships and a treaty signed opening two Japanese ports and guaranteeing safety of shipwrecked US seamen.
1854 - Nicaragua; July 9 to 15. Naval forces bombarded and burned San Juan del Norte (Greytown) to avenge an insult to the American Minister to Nicaragua.
1855 - Uruguay; November 25 to 29. United States and European naval forces landed to protect American interests during an attempted revolution in Montevideo.
1857 - Nicaragua; April to May, November to December. In May Commander C.H. Davis of the United States Navy, with some marines, received the surrender of William Walker, who had been attempting to get control of the country, and protected his men from the retaliation of native allies who had been fighting Walker.
1858 - Uruguay; January 2 to 27. Forces from two United States warships landed to protect American property during a revolution in Montevideo.
1859 - China; July 31 to August 2. A naval force landed to protect American interests in Shanghai.
1893 - Hawaii; January 16 to April 1. Marines were landed ostensibly to protect American lives and property, but with the real intention of promoting a provisional government under Sanford B. Dole and the overthrow of the Hawaiian Monarchy.
1894 - Nicaragua; July 6 to August 7. U.S. forces sought to protect American interests at Bluefields following a revolution.
1896 - Nicaragua; May 2 to 4. U.S. forces protected American interests in Corinto during political unrest.
1898 - Nicaragua; February 7 and 8. U.S. forces protected American lives and property at San Juan del Sur.
1898 - De Lôme Letter: In a private letter to a friend, Spanish minister wrote disparagingly of President William McKinley, letter stolen from Post Office in Havana and released by Cuban revolutionists.
1901 - Hay-Pauncefote Treaty. US reached agreement with British Foreign Minister nullifying Clayton-Bulwer Treaty of 1850 in return for guarantee of open passage for any nation through canal.
1901 - Platt Amendment, March 2. Cuba turned into a de facto protectorate of the United States, with provisions prohibiting said country from incurring in any debts or signing treaties with any country other than the United States, allowing further US military interventions, and setting up the Guantanamo Bay Naval Base. This situation would last until 1934.
1903 - Big Stick Diplomacy. Theodore Roosevelt refers to US policy as "speaking softly and carrying a big stick", applied the same year by assisting Panama's independence movement from Colombia. U.S. forces sought to protect American interests and lives during and following the Panamanian revolution over construction of the Isthmian Canal. With brief intermissions, United States Marines were stationed on the Isthmus from November 4, 1903, to January 21, 1914, to guard American interests.
1912-25 - Nicaragua; August to November 1912. U.S. forces protected American interests during an attempted revolution. A small force, serving as a legation guard and seeking to promote peace and stability, remained until August 5, 1925.
1912-41 - China. The disorders which began with the overthrow of the dynasty during Kuomintang rebellion in 1912, which were redirected by the invasion of China by Japan, led to demonstrations and landing parties for the protection of U.S. interests in China continuously and at many points from 1912 on to 1941. The guard at Peking and along the route to the sea was maintained until 1941. In 1927, the United States had 5,670 troops ashore in China and 44 naval vessels in its waters. In 1933, the United States had 3,027 armed men ashore. The protective action was generally based on treaties with China concluded from 1858 to 1901.
1915 - RMS Lusitania sunk off in the Irish coast by submarine under control of Captain Schweiger. The British passenger liner contained troops and ammunitions, as well as passengers. 128 Americans were killed.
1915-34 - Haiti; July 28, 1915, to August 15, 1934. U.S. forces maintained order during a period of chronic political instability.
1916-24 - Dominican Republic; May 1916 to September 1924. American naval forces maintained order during a period of chronic and threatened insurrection.
1917 - Lansing-Ishii Agreement. US recognized Japan's claim to special interests in China, particularly in contiguous territory. Objection to Japan assuming German Asian territories.
1923 - US led conference results in the Dawes Plan. Eased reparations for Germany and temporal improvement of its economic situation.
1926-33 - Nicaragua; May 7 to June 5, 1926; August 27, 1926 to January 3, 1933. The coup d’etat of General Chamorro aroused revolutionary activities leading to the landing of American marines to protect the interests of the United States. United States forces came and went intermittently until January 3, 1933.
1928 - Kellogg-Briand Pact, multilateral treaty outlawing War by moral force of 60 signatory nations.
1930 - Smoot Hawley Tariff. Rise of US tariffs; retaliation by Canada and others.
1941 - Atlantic Charter. Conferences aboard warships in Placentia Bay off Argentia, Newfoundland between FDR and Churchill resulted in (1) no territorial gains sought by US or UK, (2) territorial adjustments must conform to people involved, (3) people have right to choose their own govt. (4) trade barriers lowered, (5) there must be disarmament, (6) there must be freedom from want and fear (4 Freedoms of FDR), (7) there must be freedom of the seas, (8) there must be an association of nations.
1943 - Casablanca Conference. Roosevelt and Winston Churchill met to plan European strategy. Unconditional Surrender of axis countries demanded, USSR aid and participation, invasion of Sicily and Italy planned.
1947 - General Agreement on Tariffs and Trade. Signed in Geneva by 23 nations including the US, membership has since increased, for the purpose of eliminating trade barriers of all kinds on industrial and agricultural goods.
1947 - Marshall Plan. Reconstruction of Western European economies through loans under the auspice of the United States. Increased trade between Europe and the USA.
1948 - Berlin Blockade imposed on June 24 by the Soviet Union, blocking traffic into western sectors of Berlin, followed by Operation Vittles, US airlifted massive amounts of food, fuel and supplies into city. Soviet blockade lifted on May 12, 1949.
1949 - The United States along with eleven other nations signed the North Atlantic Treaty, creating NATO, a military alliance with the purpose of countering the USSR and its allies.
1950-53 - Korean War with the support of the United Nations. U.S. forces deployed in Korea exceeded 300,000 during the last year of the conflict.
1953 - Iran U.S. and British governments organize and give support to a coup against Prime Minister Mohammad Mosaddeq, after Iranian Oil Company is nationalized.
1954 - Guatemala. U.S. supports coup against the democratically-elected government of Jacobo Arbenz Guzmán for redistributing land held by U.S. business interests. Extensive propaganda campaign against said government.
1957 - Eisenhower Doctrine stated that the US would use armed force upon request of imminent or actual aggression, applied in Lebanon that year successfully.
1961 - Alliance for Progress. Agreement extended economic assistance to Latin American nations in exchange for land and tax reform, more democratic government, and greater stability. Lowering support and eventual cancellation after Kennedy's death.
1962 - Cuban Missile Crisis. John F. Kennedy on October 22 announced that there existed Soviet missiles in Cuba and demanded their removal while imposing an air sea blockade. Nikita Khrushchev sent two letters, one belligerent one conciliatory to Kennedy, Kennedy ignores belligerent letter and missiles are withdrawn on condition that US won't invade Cuba. Kennedy demanded onsite inspection, which was not allowed.
1964 - Brazil. Economic and diplomatic support to the overthrow of democratically-elected president João Goulart. Military support, under the name Operation Uncle Sam, was planned but ultimately not executed.
1965 - Indonesia; U.S. supports coup against Sukarno government in Indonesia.
1968 - Tet Offensive in Vietnam causes political crisis at home.
1973 - Paris Peace Treaty ends the American war in Vietnam.
1973 - Chile, September 11. U.S. supports and actively helps to organize coup against the democratically-elected government of Salvador Allende.
1975 - North Vietnam invades and conquers South Vietnam; over 1 million refugees eventually come to the US.
1975-1983 - Operation Condor. Active diplomatic and intelligence cooperation with numerous South American right-wing military juntas to help in the repression of insurgent guerrilla movements, in fact this repression extended to political dissidents of all kinds.
1979-90 - Nicaragua; U.S. supports the creation of Contras, armed groups composed mainly of defeated National Guardsmen from disposed Nicaraguan dictator Anastasio Somoza. During this campaign, the U.S. supports the military regimes in neighboring El Salvador, Guatemala, and Honduras to wage war against the Sandinista government in Nicaragua. Also see Iran-Contra Affair.
1979-80 - Iran becomes an Islamic Republic after the overthrow of U.S.-backed Shah; militants seize 63 American diplomats for 444 days during the Iran hostage crisis; U.S. seizes $12 billion in Iranian assets; American rescue effort fails; on Jan 20, 1981 hostages and assets are freed.
1980-88 - Iran-Iraq War. U.S. officially neutral in said war between Iraq (under Saddam Hussein) and Iran; US flags oil tankers to protect flow of oil in Persian Gulf, and sells arms and weaponry to both sides of the conflict.
1990 - Panama; U.S. invades country to oust dictator and former CIA-agent Manuel Noriega.
1991 - Gulf War; U.S. leads a UN-authorized coalition to repel an Iraqui invasion out of neighboring Kuwait.
1991-1993 - START accords between the United States and the Soviet Union (After 1991, Russia), both countries agree to limit the production, and reduce their stocks, of nuclear weapons and other types of ballistic weaponry.
1991-2003 - Iraq sanctions; U.S. and Britain maintain no-fly-zones in the north and south of Iraq with periodic bombings.
21st century
2003 - US-led coalition invades Iraq to overthrow Saddam Hussein. Troops remain to fight insurgency against the UN-approved elected government.
to be continued
References
Lester H Brune, Chronological History of U.S. Foreign Relations (2003), 1400 pages
Alexander Deconde, Richard Dean Burns, Fredrik Logevall, and Louise B. Ketz, eds. Encyclopedia of American Foreign Policy 3 vol (2001), 2200 pages; 120 long articles by specialists.
John E. Findling, ed. Dictionary of American Diplomatic History 2nd ed. 1989. 700pp; 1200 short articles.