The United States was condemned on many fronts for dragging its feet in entering World War I, but in truth the nation's isolationist policies were as old as the republic itself.
America's first political leaders encouraged commercial treaties and expansion of trade with other nations but discouraged political or military alliances because of their inherent dangers. One such view was expressed by George Washington, who in his 1796 farewell address advised the nation that he had helped to promote good relations with all the world's countries, particularly in regard to trade, but warned strongly against becoming involved in Europe's complicated and ever-changing political affairs.
The United States maintained an isolationist attitude for many years, preferring to expand into the sparsely populated land that spread from the Atlantic to the Pacific rather than become involved in global politics. Such an attitude also helped protect the fledgling country from European domination — always a risk when dealing with older, more established nations.
With only a few exceptions, isolationism remained a steadfast policy throughout the nineteenth century and well into the twentieth. When hostilities finally broke out in Europe in 1914, the United States assumed a stance of neutrality, despite the fact that many of its most important economic allies were fighting for their lives.
The war raged for nearly three years before U.S. troops went to Europe in the spring of 1917, provoked by attacks on merchant ships by German submarines. American anger was aggravated by the discovery of what became known as the Zimmerman note — a secret message from German foreign minister Arthur Zimmerman to his ambassador in Mexico City, instructing him to offer Mexico financial aid in exchange for an invasion of the United States. Declaring that, “the world must be made safe for democracy,” President Woodrow Wilson finally asked Congress for a declaration of war. The United States entered World War I four days later.
At the war's conclusion, America once again put up an isolationist wall. Even after just one year, the country had grown weary of fighting overseas and the Red Scare at home, and wanted nothing more to do with international politics. The men who served as president after World War I understood this sentiment and did all they could to keep the nation out of conflict. As President Warren G. Harding noted, the nation needed “not submergence in internationality but sustainment in triumphant nationality.”
The League of Nations was established in 1920 in an effort to make sure another world war would never happen. Though the League was suggested by President Woodrow Wilson, the United States did not join. The U.S. Senate, angry over being left out of treaty negotiations by Wilson, and concerned about congressional war powers, refused to ratify the Treaty of Versailles, which governed the League's covenant.