How America became a superpower

The modern United States stands as the most powerful nation in history. With over 800 military bases and 37% of global military spending, the U.S. has become the leader of a vast global system that has facilitated an era of unprecedented prosperity and relatively low conflict. To understand America’s current role in the world, we must look back to its early years, when it wasn’t a global power at all.

During the first 70 years of its existence, the U.S. expanded its territory and influence across North America, reaching the Pacific Ocean. This expansion came at the cost of the indigenous populations, who were largely decimated in the process. Yet, early Americans were divided on whether the nation should extend beyond the Pacific and Atlantic oceans. This debate became more intense after the Civil War, with figures like post-war Secretary of State Seward advocating for the U.S. to become a global power. While Seward succeeded in securing the purchase of Alaska from Russia, his attempts to acquire Greenland, Iceland, and Caribbean territories were blocked by Congress. Many Americans, particularly those in Congress, held strong anti-imperialist views, fearing the integration of “inferior” races and the impact of deeper global entanglements.

However, the late 1800s brought industrial growth, which fueled rapid economic expansion and the need for a stronger central government. This concentration of power made it easier for expansionist leaders like President William McKinley to push for U.S. influence abroad. A major turning point came in 1898 when McKinley led the U.S. into war with Spain over Cuba, despite strong opposition. The U.S. defeated the weakened Spanish empire and acquired Puerto Rico, Guam, and the Philippines. Over the next few years, the U.S. also annexed Hawaii, Wake Island, and American Samoa, while taking control of the Panama Canal Zone and sending troops to the Dominican Republic. These acquisitions established the U.S. as a true global power.

By the time of World War I, America’s global influence was undeniable. U.S. intervention helped bring an end to the war, and President Wilson played a key role at the Paris Peace Conference, where he proposed the League of Nations — an ambitious effort to reshape global politics and prevent future conflicts. However, isolationism remained strong in the U.S., and Congress blocked the country’s participation in the League.

Despite this, global events such as the rise of Hitler and the Great Depression eventually pushed the U.S. into more active involvement in world affairs. In East Asia, Japan’s growing empire posed a direct threat to U.S. territories, leading to conflict. This culminated in the attack on Pearl Harbor, drawing the U.S. into World War II. The war dramatically transformed America’s global role. The U.S. was the only major power to emerge economically intact and was the only nation with atomic weapons, giving it the unique ability to set the post-war peace terms.

The creation of the United Nations was one of the most notable examples of American influence, establishing a system of international law to prevent wars of conquest. The Bretton Woods Agreement, formed by 44 Allied nations, set up the World Bank and the International Monetary Fund, creating a global financial system to avoid another Great Depression. These institutions committed the U.S. to active involvement in global issues.

However, the Soviet Union’s emergence as a rival superpower in the aftermath of World War II created tensions. The U.S. saw Soviet expansion as a threat to the free-trading world it envisioned. This led to the formation of NATO, a military alliance aimed at preventing Soviet aggression in Europe. The U.S. also adopted a policy of “containment” to limit the spread of communism globally. This led to U.S. interventions, often covert, in countries like Iran, Afghanistan, and Nicaragua during the Cold War. The U.S. found itself entangled in alliances and conflicts worldwide.

After the fall of the Berlin Wall, the U.S. had an opportunity to withdraw from this global system, but it chose instead to maintain its military and political commitments. Presidents George H.W. Bush and Bill Clinton argued that it was in the best interest of both the U.S. and the world to continue playing an active role in global affairs. NATO expanded, and the U.S. continued supporting nations like Israel and Japan as a means of preserving peace.

This post-Cold War system of alliances and institutions has persisted, with few challenges until the rise of Donald Trump. While Trump has made contradictory statements about America’s global commitments, he has consistently argued that U.S. allies are not paying enough for protection and has questioned the value of free trade. This marks a significant departure from the consensus that has guided U.S. foreign policy since 1945, edging closer to isolationism. The question now is whether Trump will follow through on these ideas, potentially reversing decades of American institutional building and alliances. We will soon find out.