Foreign interventions by the United States
| History of the United States expansion and influence |
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| Militarism |
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| Concepts |
The United States has been involved in hundreds of interventions in foreign countries throughout its history, engaging in nearly 400 military interventions between 1776 and 2026, with half of these operations occurring since 1950 and over 25% occurring in the post-Cold War period. Common objectives of U.S. foreign interventions have historically revolved around economic opportunity, protection of U.S. citizens and diplomats, territorial expansion, counterterrorism, fomenting regime change and nation-building, promoting democracy and enforcing international law. There have been two dominant ideologies in the United States regarding foreign policy—interventionism, which encourages military and political intervention in the affairs of foreign countries—and isolationism, which discourages these.
The 19th century formed the roots of United States foreign interventionism, which at the time was largely driven by economic opportunities in the Pacific and Spanish-held Latin America along with the Monroe Doctrine, which saw the U.S. seek a policy to resist European colonialism in the Western Hemisphere. The 20th century saw the U.S. intervene in two world wars in which American forces fought alongside their allies in international campaigns against Imperial Japan, Imperial and Nazi Germany, and their respective allies. The aftermath of World War II resulted in a foreign policy of containment aimed at preventing the spread of world communism. The ensuing Cold War resulted in the Truman, Eisenhower, Kennedy, Carter, and Reagan Doctrines, all of which saw the U.S. engage in espionage, regime change, proxy wars, and other clandestine activity internationally against affiliates and puppet regimes of the Soviet Union.
After the Soviet Union collapsed in 1991, the U.S. emerged as the world's sole superpower and, with this, maintained interventionist policies in Africa, Eastern Europe, and the Middle East. Following the September 11 attacks in 2001, the Bush administration launched the "war on terror" in which the U.S. waged international counterterrorism campaigns against various extremist groups—such as al-Qaeda and the Islamic State—in various countries. The Bush Doctrine of preemptive war saw the U.S. invade Afghanistan in 2001 and Iraq in 2003. In addition, the U.S. expanded its military presence in Africa and Asia via status of forces agreements and a revamped policy of foreign internal defense.
The Obama administration's 2012 "Pivot to East Asia" strategy sought to refocus U.S. geopolitical efforts from counter-insurgencies in the Middle East to improving American diplomatic influence and military presence in East Asia. The "Pivot to Asia" fomented a policy shift towards countering China's rising influence and perceived expansionism in the South China Sea—a trajectory continued by the Trump (2017–2021, 2025–present) and Biden administrations under the Free and Open Indo-Pacific (FOIP) strategy, alongside reinforcing the first island chain. The second Trump administration introduced the Trump Corollary to the Monroe Doctrine, aiming to consolidate US dominance in the Western Hemisphere and prevent Chinese, Russian and other adversarial powers from meddling in "America's backyard." In January 2026, the US intervened in Venezuela, capturing President Nicolas Maduro and constraining his government. The next month, the United States and Israel jointly attacked Iran, killing Iranian supreme leader Ali Khamenei and other Iranian leaders, sparking the ongoing 2026 Iran conflict.
The United States Navy serves as a key element of United States global power projection and its ability to conduct foreign interventions. As a blue-water navy, it has been involved in anti-piracy activity in international and foreign territory throughout its history, from the Barbary Wars to combating modern piracy off the coast of Somalia and other regions. The United States Air Force's strategic airlift and global strike capabilities alongside clandestine activity by special operations units are two other major components in US hard power projection.