During the years between the American Civil War and the outbreak of World War I, the United States experienced no serious problems connected with its own neutral rights. While promoting its strategic interests, the United States failed in one situation to adhere strictly to its obligations as a neutral nation and to live up to its treaty obligations. During the Panamanian Revolution of 1903, the United States departed from its neutral position by preventing the landing in Panama of Colombian troops attempting to suppress the revolution. In the same action, the United States violated its treaty obligations with Colombia in a 1846 treaty that pledged the United States to guarantee the "rights of sovereignty and property" of Colombia over the Isthmus of Panama. In 1921 the United States compensated Colombia for its loss of Panama.
At the Second Hague Conference, the United States sought to secure an agreement on the rights and duties of neutrals that included the principle that had been advocated by the United States since 1784: that noncontraband neutral private property was exempt from capture. Although the conference adopted a convention on neutral rights, so many significant issues remained unresolved, such as the one of private property, that a separate meeting of the major maritime powers was organized to consider those issues. They met in London in 1908, and the following year issued the Declaration of London. The declaration provided for the most extensive and, as far as neutrals were concerned, the most liberal rules governing neutral trade that had ever been achieved. Although they did not prohibit the capture of private property, they did enumerate an extensive list of free goods and limited the principle of continuous voyage to absolute contraband. Universal acceptance of the declaration would have benefited neutral trade with belligerents, and it would have assisted those belligerents who would have profited from such trade. However, it would have restricted other belligerents in the exercise of rights previously recognized under generally acceptable rules of international law. Consequently, Britain rejected the Declaration of London, and as universal ratification was not achieved, the United States did not ratify the treaty, although the Senate had consented to it.
When World War I began the United States, under President Woodrow Wilson, issued a declaration of neutrality on 4 August 1914. Issues concerning American neutral rights arose most seriously with Britain and Germany. The British did not establish a traditional close blockade of German ports. Rather, it gradually expanded the contraband list to include goods that could be used to manufacture war materials and those that would be of significant value to the German war effort. The British also made extensive use of the doctrine of continuous voyage. The United States protested British maritime practices; however, Britain possessed a basis in international law for its policies. No precise lists of contraband had ever been universally accepted. The idea that some materials on a free list might become contraband had been a feature of treaties since the seventeenth century. During the American Civil War, the United States had added naval stores and "articles of like character with those specifically enumerated" to the contraband list. The doctrine of continuous voyage was also firmly based in international practice and had been sanctioned by the United States during the Civil War. Even under the Declaration of London (1909), in which the principle of continuous voyage was limited to absolute contraband, the legal extension of such contraband was admitted. Although the United States might have protested the extremes to which Britain carried its maritime policies, it had no solid basis in international law to deny their validity, nor did it grant to the Allies rights prohibited to the Central Powers. General American sympathy for the Allied cause, plus ties of culture and economics, precluded the United States from forcefully defending its neutral rights, or engaging in retaliation as it had during the Napoleonic Wars. Furthermore, Germany's reliance upon the submarine, which caused not only property damage but also the loss of lives, came for most Americans to overshadow any actions by Great Britain.
The conflict between the United States and Germany stemmed largely from German insistence upon the use of unrestricted submarine warfare. The United States did not oppose a German blockade of Allied ports if the blockade were proclaimed and effective, nor did it deny the right of Germany to stop neutral ships on the high seas and to seize both the cargo and the ship if it carried contraband. In an attempt to break the tightening of the British blockade and deny the British supplies from across the Atlantic, Germany—in a proclamation of 4 February 1915—declared a war zone in the waters around Britain, including the English Channel. Germany threatened to sink all merchant vessels, including neutrals, without warning or providing for the safety of passengers and crew. The United States replied on 10 March 1915 that if American ships were so destroyed or American lives lost, this would be "an indefensible violation of neutral rights" and that it would "take any steps it might be necessary to take to safeguard American lives and property."
Although early attacks on American ships prompted protests from the United States, it was not until the sinking of the British liner Lusitania on 7 May 1915, with the loss of 1,198 lives, including 128 Americans, that the American government vehemently protested. In the first Lusitania note from the Wilson government to Germany, the United States insisted that German submarines stop firing on merchant vessels. In a second Lusitania note, the United States threatened direct action if Germany did not stop its unrestricted use of the submarine against merchant vessels. In a conciliatory reply and an offer for compensation, Germany sought to defuse the situation with the United States. However, on 19 August 1915 the British liner Arabic was sunk, claiming two Americans. To stave off possible American retaliation, Germany issued the socalled Arabic Pledge, a promise that submarines would not attack passenger ships without providing warning and making provisions to rescue passengers and crews. In March 1916 a German submarine torpedoed the French liner Sussex, resulting in the injury of two Americans. From the American perspective, this appeared to be a violation of the Arabic Pledge and Wilson threatened to break off diplomatic relations. The German government once again tried to assuage the Americans by reaffirming the Arabic Pledge.
Germany had failed to achieve military victory by the summer of 1916. With serious political and social problems developing at home, and the German high command concerned about the will of the German people to continue the war, a last major all-out offensive on the western front was planned for the spring of 1917. In a desperate gamble designed to deprive the Allies of vital foodstuffs and materials, the German government resumed unrestricted submarine warfare on 1 February 1917, fully aware that this was likely to bring the United States into the war on the side of the Allies. The United States broke off diplomatic relations with Germany. Following the sinking of several U.S. ships by German submarines in March, the United States declared war on Germany on 6 April 1917. Several factors contributed to American entry into the war, but preservation of neutral rights was a key one.
By the end of World War I, President Wilson had determined that in the interests of humanity, as well as national security, a new approach to world peace was necessary. He was able to convince most of the major statesmen in the world to accept this need and the Covenant of the League of Nations was the outcome. The signatories to the covenant agreed "to preserve as against external aggression the territorial integrity and existing political independence of all Members of the League." If a member of the league resorted to war in disregard of its obligations under the covenant, then members of the league would prohibit all trade and financial relations with the covenant-violating state. Furthermore, nonmembers of the league would also be required to abide by these sanctions. Thus, the traditional rights of neutrals to trade with belligerents would be prohibited. However, when Japan violated the Covenant in 1931 by invading Manchuria, and Italy followed in 1935 with its invasion of Abyssinia, the league failed to impose sanctions at all in the first case, and only partially and ineffectively in the second. The league system of collective security collapsed. The extent to which American refusal to join the league contributed to the failure of the League of Nations failure is debatable.
In the twenty years after World War I, the United States rejected the League of Nations, pursued nationalistic economic policies, promoted naval arms limitations, and signed feeble and useless pacts, such as the Kellogg-Briand Pact of 1928 and the London Naval Treaties of 1930 and 1936. At the same time it focused overwhelmingly on domestic affairs and displayed apparent indifference to the moral and political disintegration of world order. When the specter of another world war arose, the nation naively sought to isolate itself from world affairs and pursued safety in the abandonment of its once-cherished neutral rights, for which it had fought two foreign wars. American neutrality had never meant simply noninvolvement in world affairs. Rather, it meant the determination to support the rights of its people under rules of international law that, in turn, would contribute to the civilized conduct of nations.
This reversal of America's traditional policy was accomplished through a series of congressional neutrality acts commencing in 1935 and reaching their most comprehensive form in the Neutrality Act of 1937. Believing that American insistence upon its historical defense of neutral rights, along with the greed of bankers and arms merchants, had helped to suck the United States into World War I, Congress passed legislation that in essence repudiated traditional American views of neutral rights. Under these acts, if the president determined that a "state of war" existed among two or more foreign states, American citizens were prohibited from exporting arms, munitions, or implements of war to belligerents or to neutrals for transshipment to belligerents, or to a state where civil strife existed. The selling of securities or making of loans was prohibited, as was travel by American citizens on belligerent ships. American merchant vessels were not to be armed, and they were prohibited from carrying materials of war. Nonprohibited goods could be sold to belligerents, provided the title to them was transferred before being transported abroad. By renouncing its historical interpretation of neutral rights, so the thinking went, the United States could hope to escape being drawn into another foreign war.
Commensurate with this "new neutrality" policy, the United States moved to strengthen relations with Latin American nations. The Neutrality Act of 1937 specifically exempted Latin American states from its application in case of war between one or more of them and a non-American state. In a series of conferences between the United States and Latin America, beginning at Buenos Aires in 1936, the American republics agreed to preserve their neutrality and to act in concert in the event of any threat to their safety or independence. However, when war broke out in Europe and the United States began to alter its neutrality policies, it acted independently of its Latin American neighbors. During World War II some Latin American states that remained neutral referred to their status as "nonbelligerency," a term without precise meaning in international law, but in reality an extension of commercial rights to the United States not accorded to other belligerents.
The "new neutrality" policy failed for many reasons. In actuality, under President Franklin D. Roosevelt the United States was not about to stand idly by and let the world be dominated by the aggressors who had signed the Tripartite Pact. Presidential acts as well as congressional measures eroded the new policy. President Roosevelt refused to recognize that a state of war existed between Japan and China, or between Russia and Finland. In the destroyers-for-bases deal of 1940, he sold or traded World War I–vintage warships to Great Britain, and extended the Monroe Doctrine to include the mid-Atlantic. In 1939 Congress repealed the arms embargo provisions of the Neutrality Act of 1937, cut trade with Japan, and passed the Lend-Lease Act of 1941, which in effect made the United States an unofficial ally of the nations opposing the Axis. By the end of October 1941, a virtual state of war existed between Germany and the United States, with President Roosevelt convinced that formal war would break out over some incident in the Atlantic between the two countries. However, as Japan was bent upon establishing its "greater East Asia co-prosperity sphere," Roosevelt—in an effort to pressure the Japanese to relinquish their conquests in China and Southeast Asia—ultimately cut off all exports to Japan. Convinced that the United States meant to strangle Japan, its government in 1941 undertook plans to attack and, if possible, destroy the American Pacific fleet. When the attack on Pearl Harbor came on 7 December 1941, followed in quick succession with an American declaration of war on the Japanese Empire and German and Italian declarations of war on the United States, history witnessed the end of the United States as a neutral nation, at least in a traditional sense.
Prior to the formal conclusion of World War II, the United States reversed its traditional policy for the second time since 1920 by playing the leading role in establishing the United Nations. While the Charter of the United Nations differed significantly from the Covenant of the League of Nations, its impact on the concept of neutrality was basically the same. The Security Council of the United Nations was assigned the primary responsibility for world peace and for taking action against a state deemed to have threatened the peace of the world. Such action could be in the form of economic sanctions, which have had the effect of eroding the historical rights of neutrals.
Because of the preeminent political, economic, and military position of the United States in world affairs since the end of World War II, the nation was involved in numerous armed conflicts, some of which, like Vietnam, were protracted, even though war was never declared. The United States intervened, covertly and overtly, throughout the world where it felt its interests, or its vision of a desirable world order, was threatened, with little regard to concepts of neutral rights. In other situations, such as in the Korean War or the Persian Gulf War, the United States operated under the umbrella of the United Nations. Neutrality, a cornerstone of American foreign policy since before the establishment of the republic, was no longer relevant. Although there were some in the United States who hoped the country could once again return to an independent, neutral position in the world, President Harry S. Truman and other policymakers pursued international economic and military policies that were essential for the promotion of international trade, expansion of democratic ideals, prevention of another postwar depression, and stopping the spread of communism.
The wartime conferences at Yalta and Potsdam, followed by a series of Council of Foreign Ministers' meetings, were characterized by mutual suspicion and mistrust, and foreshadowed the rivalry that would come to be called the Cold War. Although the Western powers were already skeptical of Soviet intentions in territories they had liberated in Eastern Europe, the issue over Iran gave cause for Western alarm. In late 1945 a communist-orchestrated revolution broke out in the oil-rich region of Azerbaijan in northern Iran, particularly when the Soviets sent troops and arms to assist the revolutionaries. In addition, the Soviets failed to pull out of Iran in March 1946, as they had agreed previously. Although the Soviets withdrew in May after receiving minor concessions from Iran, their actions in the Near East, commensurate with increasing tensions in Eastern Europe, helped convince Truman that Soviet leader Joseph Stalin meant no good. Winston Churchill's Iron Curtain speech in March 1946, a United States decision against a loan to the Soviets, the termination of German reparations to the USSR from the American occupation zone in Germany, American promotion of the Baruch Plan to control atomic weapons testing and development, and other issues concerning Germany heightened the feelings of mistrust between the Western powers and the Soviets.
The United States was anything but neutral in the Greek civil war and was extremely concerned about Soviet pressure on Turkey. If successful there, the Soviets would gain access to the Persian Gulf, the Mediterranean, and the oil-rich Middle East. Western Europe would most likely collapse and the British Mediterranean barrier to Soviet expansion and influence would be breached if Greece and Turkey fell.
Fighting had broken out in Greece in December 1944 between rightists, who tended to support the return of the monarchist government in exile, and communists. Under the terms of an uneasy truce reached at Varkiza in February 1946, an election was to be held to determine the form of government, and then another election was to take place for a constituent assembly. However, in the days before the election the conservative government repressed the opposition to the monarchy. By the time the election was to occur in March, both the British and the Americans had reneged on the procedures agreed to at Varkiza. Although a general election and plebiscite were held, the communists boycotted them. The results seemingly indicated support for the return of the king. These actions set off a civil war that was largely internal in origin. Many Americans, however, assumed it was Soviet coordinated, and by the spring of 1947 the situation seemed critical.
The gravity of the Greek situation, coinciding as it did with Soviet demands on Turkey and the notification by Britain in the fall of 1947 that it could no longer afford to maintain its commitments to Greece and Turkey, compelled President Truman to act. The result was what became known as the Truman Doctrine, the provisions of which were enumerated before a joint session of Congress on 12 March 1947. In addressing Congress, Truman stated "that it must be the policy of the United States to support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures." The Truman Doctrine, although initially directed at Greece and Turkey, had as its primary goal the "containment" of communism. The Truman Doctrine represented a watershed in American history. This policy it represented became the justification for American intervention, covertly and overtly, in the internal affairs of nations throughout the world, and it formed the basis for the establishment of regional security treaties that were directed against the Soviet Union and its perceived allies. The United States sought to contain communism in Europe through such measures as the Truman Doctrine, the Marshall Plan, and the formation of NATO, and virtually every other part of the world witnessed American interventions calculated to stop communism's spread.
In Asia the United States' major concern was China. As World War II came to an end, civil war in China between the nationalist armies under Chiang Kai-shek, and the communists under Mao Zedong, resumed. Each side hoped to secure territory and supplies by accepting the surrender of Japanese troops in China and Manchuria. Although outwardly encouraging talks between the two rival factions, the United States nonetheless moved its troops and transported nationalist soldiers into key eastern and northern Chinese cities in order to accept the Japanese surrender. In northern China and Manchuria, fighting broke out between the two groups. The communists were assisted by the Soviets in Manchuria, and the nationalists were assisted by the Americans. Although American lend-lease assistance to its other allies had ended, it was continued in the case of China. In January 1946 it seemed that there was a glimmer of hope when President Truman sent General George C. Marshall to China as a special envoy to get the two sides to talk. The truce, however, proved illusory as each side maneuvered to gain the upper hand. The resulting civil war was one of the most bitter and devastating in modern history. In the end, Chiang Kaishek could not command the same level of popular support as Mao and the communists proclaimed victory in October 1949, with Chiang fleeing to Taiwan. The "loss" of China subjected the Truman administration to severe political criticism for not doing enough for China. In the final analysis, short of an all-out effort to support the Nationalists, nothing could have been done to prevent their defeat. Also, for Truman the most important foreign policy priority was shoring up Europe against Soviet threats. The thirty-year treaty of alliance negotiated by Mao and the Soviet Union in 1950 was further evidence to many Americans that worldwide communism was being orchestrated by the Soviets. As far as China was concerned, American efforts to contain communism had failed.
For the United States, intervention in Asian affairs would prove extremely frustrating. Under the umbrella of the United Nations, the Cold War suddenly became a hot war with the eruption of the Korean conflict in 1950, and at the beginning of the twenty-first century the peace between North and South Korea remained precarious. In Vietnam, the United States—influenced by the domino theory and convinced of its ability to impose an outcome because of its superior strength—foolishly involved itself in what was essentially a civil war in Vietnam. For two decades the United States was caught up in a quagmire that, in the end, witnessed consolidation of the country by the communists. What the United States had tried so hard to prevent came about anyway.
In the Western Hemisphere, the United States did not hesitate to intervene in the internal affairs of governments closer to its borders than those of Asia, Europe, the Middle East, or Africa. In countries such as Nicaragua, the United States supported right-wing dictators including General Anastasio Somoza. In Chile the Central Intelligence Agency played a significant role in a coup that saw the overthrow and subsequent death of the popularly elected Marxist president Salvador Allende, who was succeeded by the anticommunist and repressive General Augusto Pinochet. The United States openly intervened in Guatemala, the Dominican Republic, and other countries because of the belief that American interests were greatly threatened by governments that included communists or suspected communists. However, the stakes were never so high as they were in Cuba, first with the Bay of Pigs invasion in 1961, then with the Cuban Missile Crisis of October 1962, which saw the world come to the brink of nuclear war as the Americans and Soviets stared down each other.
In the last decades of the twentieth century, the United States did not hesitate to continue intervening in the internal affairs of numerous nations around the word. However, there have been occasions where it sought to maintain the outward appearance of neutrality, particularly in the case of the Iran-Iraq War (1980–1988). This war threatened to drag in other nations in a geopolitically sensitive part of the world. Passage through the Persian Gulf was threatened, which in turn posed a serious threat to oil interests. While the Soviet Union shrewdly tried to cater to both sides, the United States claimed it was neutral in the conflict. Clearly there was no love lost with Iran, what with the Iran hostage crisis still fresh in Americans' minds, and relations with Iraq had only recently improved after the State Department removed Iraq from the official list of nations that sanctioned terrorism. Although publicly opposed to arms sales to Iraq, the United States nonetheless sent a large quantity of arms and supplies to Iraq's ruler, Saddam Hussein. As the administration of President Ronald Reagan became more involved in the Middle East, its preference for Iraq over Iran became evident. Ironically, in the subsequent Gulf War of 1991, the United States under President George H. W. Bush put together a United Nations coalition of forty-eight countries against Hussein.
It may be premature to suggest that the concept of neutrality has come full circle since the Treaty of Westphalia and that the historical rights of neutrals under international law no longer exist. Conceivably, a war could take place in which the United Nations would not interfere and belligerents and neutrals would assert their traditional rights. However, given the realities of the modern world, particularly since the end of World War II, and the proliferation of nuclear weapons, this does not seem to be a likely prospect. In the years since 1941, the traditional concept of American neutrality seems to have been irreversibly transformed.