U.S. International Relations

U.S. international relations shaped the global order after World War II and have become increasingly important in the current era of multipolar competition. As the sole superpower since 1991, the country maintains 750 foreign military bases in 80 countries, leads the world’s largest military alliance, NATO, with 32 members, and plays a core role in international institutions from the United Nations to the IMF, World Bank, and WTO.

Current foreign policy faces major challenges from the rise of China, Russia’s destabilisation of Europe, Iran and North Korea’s development of nuclear weapons, and transnational challenges such as climate change, pandemics, and cybersecurity. This article synthesises foreign policy based on data from the U.S. Department of State and policy research organisations. This is an extension of the page United States overview, linked to history and U.S. politics.

Foreign policy structure

U.S. international relations are managed by four main government agencies, with the President as the final decision-maker under the authority of Commander-in-Chief of the military and diplomatic representative.

Department of State and Department of Defense

The U.S. Department of State is the agency responsible for diplomatic relations, with approximately 76,000 employees and a global network of 270 embassies and consulates. Marco Rubio has been Secretary of State since January 2025. The Department of Defense (DOD) has 3.2 million personnel (1.4 million active-duty military + 800,000 reserve + 770,000 civilian), headquartered at the Pentagon. The 2024 defence budget reached US$877 billion — three times that of China and larger than the next 10 countries combined. This is the core of military power in foreign policy.

National Security Council and CIA

The National Security Council (NSC) is the advisory body to the President on security and foreign policy, led by the National Security Advisor (Mike Waltz from 2025). The NSC coordinates relevant departments and agencies. The Central Intelligence Agency (CIA) is the most important intelligence agency, collecting foreign intelligence through a global network of agents. The Office of the Director of National Intelligence (ODNI) coordinates 18 intelligence agencies including the NSA, DIA, and FBI Intelligence Branch. The intelligence budget was US$76 billion in 2024.

Role of the President

The Constitution grants the President supreme military command and the power to negotiate international treaties (requiring two-thirds Senate approval). The President may sign executive agreements without Senate approval, which are far more common than formal treaties. War powers: only Congress can officially declare war (which it has not done since World War II), but the President can deploy troops under the War Powers Resolution of 1973 for 60 to 90 days. The Trump Doctrine during his second term emphasises “America First” through tariff policies, bilateral negotiations, and reduced multilateral commitments.

NATO and European allies

The North Atlantic Treaty Organization (NATO) is the largest and oldest military alliance, serving as the backbone of United States international relations with Europe since 1949.

NATO Structure

NATO has 32 members in 2025 following the accession of Finland in 2023 and Sweden in 2024 due to the threat from Russia. Its headquarters are in Brussels, Belgium. The collective defence mechanism under Article 5 states that “an attack on one member is an attack on all”. It has been invoked only once, following 11 September 2001. The United States contributes 70% of NATO costs, maintains 100,000 troops in Europe, and stations 200 tactical nuclear weapons across five European countries (Germany, Italy, Belgium, the Netherlands, and Türkiye).

Ukraine War

Following the Russian invasion of Ukraine on 24 February 2022, the United States and NATO became the primary military donors to Ukraine. Total United States aid to Ukraine reached US$175 billion by early 2025, encompassing weapons, economic aid, and humanitarian assistance. The second Trump administration is negotiating an end to the war with an approach different from Biden’s, exerting pressure on both Ukraine and Russia to reach an agreement. This conflict will reshape United States international relations with Eastern Europe for decades to come.

EU and UK Relations

The European Union is the largest trading partner, with US$1.2 trillion in trade volume in 2024. Following Brexit in 2020, the United Kingdom has pursued a special bilateral relationship with the United States. France and Germany are two primary partners within NATO. However, the second Trump administration has caused tension with the EU through threats of a 20% tariff on all imports and pressure on Europe to contribute more to NATO, targeting 5% of GDP instead of the current 2%. This represents a major challenge to the transatlantic relationship of the past 80 years.

Indo-Pacific allies

The Indo-Pacific region is a top strategic priority in United States international relations for the 21st century, driven by competition with China and the region’s economic importance.

Bilateral Treaties

The United States has five formal defence treaties in the Indo-Pacific: Japan (1951, with 54,000 US troops), South Korea (1953, with 28,500 troops), the Philippines (1951), Thailand (1954), and Australia (ANZUS 1951). Taiwan is governed by the Taiwan Relations Act of 1979, which is not a treaty but commits the US to military support. Singapore has a strategic base agreement. Total United States military personnel in the Indo-Pacific stand at approximately 130,000. The 7th Fleet, based in Yokosuka, Japan, is the largest overseas fleet, comprising 70 warships including the aircraft carrier USS George Washington.

QUAD and AUKUS

The Quadrilateral Security Dialogue (QUAD) comprises the United States, Japan, Australia, and India, enhancing cooperation for a free and open maritime security architecture. It has held annual summits since 2021. AUKUS is a trilateral security pact between Australia, the UK, and the USA signed in 2021, which includes sharing nuclear submarine technology under which Australia will acquire eight nuclear submarines by 2040. The Indo-Pacific Economic Framework (IPEF) is a regional economic framework launched by Biden in 2022 with 14 members, including Vietnam.

Relations with ASEAN

ASEAN has been a comprehensive strategic partner since 2022. Total United States-ASEAN trade volume reached US$442 billion in 2024, exceeding that with China individually. Vietnam, Singapore, Indonesia, Thailand, and the Philippines are five primary ASEAN partners. Singapore leads in foreign direct investment into the US from ASEAN. However, ASEAN holds diverse viewpoints: some members such as Cambodia, Myanmar, and Laos are pro-China, while others such as the Philippines, Singapore, and Vietnam seek to balance between the two superpowers, clearly shaping United States policy in the region.

Relations with China

China is the most significant power challenging the position of the United States and serves as a central focus of United States international relations in the 21st century. This complex relationship combines strategic competition with economic interdependence.

Trade War

The trade war began during the first Trump administration in 2018 with 25% tariffs on US$360 billion of imported goods from China. Biden maintained most tariffs and added duties on electric vehicles, lithium batteries, and semiconductors. The second Trump administration escalated matters from 2025 with a 60% tariff on all Chinese goods. China retaliated with tariffs on soybeans, aircraft, and pharmaceuticals. Bilateral trade reached US$758 billion in 2024, remaining the world’s largest trading relationship despite the prolonged trade war. The US recorded a trade deficit of US$295 billion with China.

Semiconductor and Technology Competition

Semiconductors represent the most critical technological battleground. The CHIPS Act of 2022 allocated US$52.7 billion in subsidies to build domestic semiconductor manufacturing plants, reducing reliance on Taiwan and Asia. The Department of Commerce banned the export of advanced Nvidia and AMD chips to China. China responded by banning the export of rare earths, gallium, and germanium. As a result, TSMC is building a US$65 billion plant in Arizona, Samsung is building a US$17 billion facility in Texas, and Intel is expanding in Ohio. This marks a major shift in global supply chains.

The Taiwan Issue

Taiwan is the most potential flashpoint that could lead to a US-China conflict. The United States follows a “One China” policy while not officially recognising Chinese sovereignty over Taiwan. The Taiwan Relations Act of 1979 commits the US to providing defensive weapons. Xi Jinping has stated that Taiwan will be reunified by 2049, without ruling out the use of force. Biden has asserted on four occasions that the US would defend Taiwan if China attacked, which contradicts the traditional policy of “strategic ambiguity”. Taiwan produces 65% of global semiconductors and 90% of advanced chips, meaning a conflict would devastate the global economy.

Relations with Russia

United States-Russia relations are at their lowest point since the end of the Cold War, particularly following the 2022 invasion of Ukraine. This remains one of the most sensitive challenges in United States international relations.

Sanctions and Confrontation

The United States has imposed over 18,000 sanctions on Russian individuals and entities since 2022, representing the largest sanctions package in history. Thousands of Western businesses have withdrawn from Russia, including McDonald’s, Starbucks, Apple, IKEA, BMW, and Ford. US$300 billion of Russian foreign exchange reserves have been frozen in Western banks. Nonetheless, the Russian economy has sustained itself through oil exports to China and India, alongside strengthened relations with China and North Korea. Russian GDP grew by 3.6% in 2024, outperforming expectations.

Nuclear Balance

The United States and Russia possess 90% of the world’s nuclear weapons, with approximately 5,500 warheads each. The New START strategic arms control treaty expires in February 2026, and Putin has announced it will not be extended. During his second term, Trump has been negotiating a new treaty that would include China, which currently holds 600 warheads and is expanding rapidly. The risk of a new nuclear arms race is increasing, presenting a major security risk to United States foreign policy and global security.

Middle East and Israel

The Middle East is a region with a long history of foreign policy involvement driven by oil, Israeli security, counter-terrorism, and competition with Iran.

Strategic Ally Israel

Israel has been the closest ally in the Middle East since 1948, receiving military aid of US$3.8 billion per year under a 10-year Memorandum of Understanding. Following the Hamas attack on 7 October 2023, the United States increased aid by an additional US$14 billion in 2024. Iron Dome, David’s Sling, and Arrow are three missile defence systems co-developed by the US and Israel. Israel is the only non-NATO nation to receive the F-35. This relationship generates internal domestic controversy within the United States regarding Palestinian policy and the Gaza conflict.

Competition with Iran

Iran is the primary regional adversary. The 2005 JCPOA (Iran nuclear agreement) achieved by Obama was abandoned by Trump in 2018, and Biden was unable to restore it. Iran currently enriches uranium to 60%, close to the 90% weapons-grade level. Tehran supports the “Axis of Resistance” groups: Hamas in Gaza, Hezbollah in Lebanon, the Houthis in Yemen, and Shia militias in Iraq and Syria. In 2024, the United States and Israel struck Iranian bases in Syria and Lebanon. Iran launched 300 missiles and drones at Israel in April and October 2024.

Abraham Accords and Saudi Arabia

The 2020 Abraham Accords, brokered by Trump, saw Israel normalise relations with the UAE, Bahrain, Morocco, and Sudan. This represents a major breakthrough in Israel-Arab relations. Saudi Arabia was the next target, but this has been delayed by the war in Gaza. Saudi Arabia is a major partner for oil and arms, having purchased US$65 billion in weapons from the US between 2017 and 2024. However, Saudi Arabia is diversifying its partners, establishing close ties with China and signing multiple agreements to settle oil payments in yuan rather than US dollars.

Latin America and Africa

Latin America has traditionally been the “backyard” of the United States under the 1823 Monroe Doctrine. Africa is the new battleground in the competition for influence with China and Russia.

Mexico and Canada

Mexico and Canada are the two most important trading partners, both having signed the USMCA (United States-Mexico-Canada Agreement) in 2020 to replace NAFTA. Total trilateral trade reached US$1.8 trillion in 2024, the largest of any free trade area. However, the second Trump administration is experiencing tensions with both countries over threats of 25% tariffs related to immigration and fentanyl. Mexico is the largest trading partner of the US (US$840 billion in 2024), surpassing China.

Venezuela, Cuba, and leftist nations

Venezuela under Maduro is the primary adversary in Latin America. The United States has imposed heavy sanctions since 2019 and supported the opposition, first Juan Guaidó (2019–2022) and subsequently Edmundo González (2024, following a fraudulent election). 7.7 million Venezuelans have left the country, with 800,000 arriving in the United States. Cuba has remained under embargo since 1962. Cuba sends 8,000 medical personnel abroad in exchange for foreign currency. US policy toward this region is complex due to the second “Pink Tide” wave, involving leftist governments in Brazil (Lula), Mexico (López Obrador and now Sheinbaum), Colombia (Petro), Chile (Boric), and Honduras (Castro).

Africa and competition with China

Africa is a region where China is currently outpacing the United States in influence. China has invested over US$170 billion in Africa through the Belt and Road Initiative (BRI). The United States has responded through Prosper Africa, PEPFAR (an HIV/AIDS programme with US$100 billion spent), and Power Africa. However, the US aid budget for Africa (US$6–8 billion per year) is significantly smaller than China’s. Several African nations, such as Mali, Niger, and Burkina Faso, expelled US troops and invited Russia’s Wagner Group to replace them between 2023 and 2024.

Relations with Vietnam

Vietnam is a particular bright spot in US foreign policy in Southeast Asia. The relationship has evolved from enemies during the Vietnam War to a comprehensive strategic partnership in just 30 years.

History of relations

Diplomatic relations between Vietnam and the US were officially normalised on 12 July 1995 under President Bill Clinton, ending a 20-year embargo. Five subsequent milestones include: the Bilateral Trade Agreement (BTA) in 2000, Vietnam’s accession to the WTO in 2007 with US support, the Comprehensive Partnership in 2013, the Comprehensive Strategic Partnership in September 2023 (the highest level, equal to China and Russia), and the establishment of the Defence Policy Dialogue Mechanism in 2024.

Vietnam-US trade

According to the USTR, total Vietnam-US trade reached US$155.1 billion in 2024, an increase of 20.5% compared to 2023. Vietnam exported US$136.6 billion and imported US$13.1 billion, creating a trade surplus of US$123.5 billion, the third largest with the US after China and Mexico. The United States is Vietnam’s largest export market, accounting for 29% of total export turnover. Major exports include electronics, textiles, footwear, wood, and seafood. Major imports include aircraft, soybeans, chemicals, and automobiles. Details on the United States economy and trade relations are available on PLI.

Defence and security cooperation

Defence cooperation has developed strongly since 2016, when Obama lifted the arms embargo. Vietnam has received decommissioned US Coast Guard patrol vessels and engaged in training and joint exercises. In 2023, Vietnam Airlines signed a contract to purchase 50 Boeing 737 MAX aircraft worth US$7.5 billion. In 2024, US Secretary of Defence Lloyd Austin visited Vietnam and signed a bilateral military cooperation treaty. The US and Vietnam frequently cooperate on South China Sea security in response to China’s actions.

Vietnamese community and investment

The 2.3 million-strong Vietnamese community serves as an important bridge in bilateral relations. California, Texas, and Florida are the three states with the largest communities. US FDI in Vietnam reached a cumulative US$11.8 billion in 2024, ranking 11th among investing countries. Intel built a US$1.5 billion semiconductor plant in Ho Chi Minh City. Samsung (South Korea) and Foxconn (Taiwan) have invested billions of dollars in Vietnam to manufacture for the US market, making Vietnam a key link in the “China+1” supply chain. This is also why many Vietnamese are interested in residency by investment in the United States via EB-5, EB-1, and EB-2 NIW pathways.