WORLD WAR I AND AMERICAN ISOLATIONISM
The United States' participation in World War I convinced many that the long-cherished position of American isolationism should be embraced even more fervently in the world changed by the first global conflict on such a massive scale. The discussion intensified at the time when the United States entered World War I and continued even in light of wide political and popular support for the U.S. entry into the Great War. Despite common reservations about the United States breaking its tradition of staying away from global entanglements, in January 1918, President Woodrow Wilson gave his famous Fourteen Points speech, in which he delineated principles for world peace that were to be used for peace negotiations in order to end World War I. One of the points proposed in the speech was the establishment of the League of Nations - an international organization whose principal mission was to maintain world peace. The Fourteen Points speech was the only explicit statement of war aims by any of the nations fighting in World War I. While European powers allied with the United States welcomed the speech, some of the most influential European leaders considered it too idealistic.
ISOLATIONISM AFTER WORLD WAR I
Despite the United States participation in World War I and Wilson's international efforts to establish a new, peaceful global order, non-interventionist tendencies of US foreign policy were in full force in the aftermath of the war. The Senate rejected the Treaty of Versailles, which automatically rejected the United States' membership in the League of Nations. A group of Senators known as the Irreconcilables, identifying with William Borah and Henry Cabot Lodge, two prominent Republican politicians known for their commitment to isolationism, had objected the clauses of the treaty which compelled America to come to the defense of other nations. The results of the 1920 elections, with the victory of Republican Warren G. Harding supporting American opposition to the League of Nations, proved that the isolationist stand enjoyed substantial support among ordinary Americans.
Although the United States was unwilling to commit to the League of Nations, the country followed ambiguous foreign policy and signed a number of international treaties and agreements. Congress passed the Knox–Porter Resolution bringing a formal end to hostilities between the United States and the Central Powers (signed into law by President Harding in 1921). Soon after, the US–German Peace Treaty of 1921 was signed in Berlin, the US–Austrian Peace Treaty of 1921 was signed in Vienna, and the US–Hungarian Peace Treaty of 1921 was signed in Budapest. In August 1928, Germany, France and the United States signed the Kellogg-Briand Pact, brainchild of American Secretary of State Frank Kellogg and French Foreign Minister Aristide Briand (following the original signatories, other nations joined, eventually reaching the number of 62). The pact aimed to outlaw war and show the United States' commitment to international peace. However, it did not hold the United States to the conditions of any existing treaties, it still allowed European nations the right to self-defense, and it stated that if one nation broke the Pact, it would be up to the other signatories to enforce it. The Kellogg-Briand Pact was more of a sign of good intentions on the part of the US, rather than a legitimate step towards the sustenance of world peace.
Non-interventionism or isolationism took a new turn during the Great Depression. President Herbert Hoover repeated the United States' commitment to isolationism while his successor, Democrat Franklin Delano Roosevelt, translated this commitment into a number of foreign policy decisions, including the introduction of Good Neighbor Policy in Latin America. The policy aimed to replace earlier military interventions of the United States in Latin America with the principle of non-intervention and non-interference in the domestic affairs of Latin America. The attention of the country focused now mostly on addressing the problems of the national economy. The rise of aggressive expansionism policies by Fascist Italy and the Empire of Japan led to conflicts such as the Italian conquest of Ethiopia and the Japanese invasion of Manchuria. These events led to rhetorical condemnations by the League of Nations and official American response was muted. America also did not formally take sides in the brutal Spanish Civil War.
While the U.S. Congress passed a number of so-called neutrality acts in the 1930s, fascism in Europe gained massive influence and the continent was on the brink of war. When in 1939 Germany invaded Poland, marking the outbreak of World War II, Americans were divided over the question of non-interventionism. The basic principle of the interventionist argument was fear of German invasion. By the summer of 1940, France suffered a stunning defeat by Germans, and Britain was the only democratic enemy of Germany. In a 1940 speech, Roosevelt argued, "Some, indeed, still hold to the now somewhat obvious delusion that we … can safely permit the United States to become a lone island … in a world dominated by the philosophy of force." A national survey found that in the summer of 1940, 67% of Americans believed that a German-Italian victory would endanger the United States, that if such an event occurred 88% supported "arm[ing] to the teeth at any expense to be prepared for any trouble", and that 71% favored "the immediate adoption of compulsory military training for all young men."
However, there were still many who held on to non-interventionism. Although a minority, they were well organized, and had a powerful presence in Congress. Ultimately, the ideological rift between the ideals of the United States and the goals of the fascist powers empowered the interventionist argument. In 1941, the actions of the Roosevelt administration made it more and more clear that the United States was on a course to war. This policy shift, driven by the President, came in two phases. The first came in 1939 with the passage of the Fourth Neutrality Act, which permitted the United States to trade arms with belligerent nations, as long as these nations came to America to retrieve the arms, and pay for them in cash. The second phase was the Lend-Lease Act of early 1941. The act allowed the President "to lend, lease, sell, or barter arms, ammunition, food, or any 'defense article' or any 'defense information' to 'the government of any country whose defense the President deems vital to the defense of the United States.'" American public opinion supported Roosevelt's actions.
Isolationist Sentiments
An anti-war protest sign prior to U.S. entry into WWII, circa 1942.