Foreign policy of the United States in the context of "Foreign Affairs"

The United States Navy (USN) is the maritime service branch of the United States Armed Forces and the naval warfare force of the United States. It is the world's most powerful navy with the largest displacement, at 4.5 million tons in 2021. It has the world's largest aircraft carrier fleet, with eleven in service, one undergoing trials, two new carriers under construction, and six other carriers planned as of 2024. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the U.S. Navy is the third largest of the United States military service branches in terms of personnel. It has 299 deployable combat vessels and about 4,012 operational aircraft as of 18 July 2023. The U.S. Navy is a part of the United States Department of Defense and is one of six armed forces of the United States and one of eight uniformed services of the United States.

The United States Navy traces its origins to the Continental Navy, which was established during the American Revolutionary War and was effectively disbanded as a separate entity shortly thereafter. After suffering significant loss of goods and personnel at the hands of the Barbary pirates from Algiers, the United States Congress passed the Naval Act of 1794 for the construction of six heavy frigates, the first ships of the Navy. The United States Navy played a major role in the American Civil War by blockading the Confederacy and seizing control of its rivers. It played the central role in the World War II defeat of Imperial Japan. The United States Navy emerged from World War II as the most powerful navy in the world, succeeding the British Navy. The modern United States Navy maintains a sizable global presence, deploying in strength in such areas as the Western Pacific, the Mediterranean, and the Indian Ocean. It is a blue-water navy with the ability to project force onto the littoral regions of the world, engage in forward deployments during peacetime and rapidly respond to regional crises, making it a frequent actor in American foreign and military policy.

The United States Intelligence Community (IC) is a group of separate U.S. federal government intelligence agencies and subordinate organizations that work to conduct intelligence activities which support the foreign policy and national security interests of the United States. Member organizations of the IC include intelligence agencies, military intelligence, and civilian intelligence and analysis offices within federal executive departments.

The IC is overseen by the Office of the Director of National Intelligence (ODNI), which is headed by the director of national intelligence (DNI) who reports directly to the president of the United States. The IC was established by Executive Order 12333 ("United States Intelligence Activities"), signed on December 4, 1981, by President Ronald Reagan. The statutory definition of the IC, including its roster of agencies, was codified as the Intelligence Organization Act of 1992 (Pub. L. 102–496, H.R. 5095, 106 Stat. 3188).

The United States National Security Council (NSC) is the national security council used by the president of the United States for consideration of national security, military, and foreign policy matters. Based in the White House, it is part of the Executive Office of the President of the United States, and composed of senior national security advisors and Cabinet officials.

Since its inception in 1947 by President Harry S. Truman, the function of the council has been to advise and assist the president on national security and foreign policies. It also serves as the president's principal arm for coordinating these policies among various government agencies. The council has subsequently played a key role in most major events in U.S. foreign policy, from the Korean War to the war on terror.

The Truman Doctrine is a U.S. foreign policy that pledges American support for U.S.-aligned nations against alleged authoritarian threats. The doctrine originated with the primary goal of countering the growth of the Soviet bloc during the Cold War. It was announced to Congress by President Harry S. Truman on March 12, 1947, and further developed on July 4, 1948, when he pledged to oppose the communist rebellions in Greece and Soviet demands on Turkey. More generally, the Truman Doctrine implied U.S. support for other nations threatened by Moscow. It led to the formation of NATO in 1949. Historians often use Truman's speech to Congress on March 12, 1947, to date the start of the Cold War.

Truman told Congress that "it must be the policy of the United States to support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures." Truman contended that because totalitarian regimes coerced free peoples, they automatically represented a threat to international peace and the national security of the United States. Truman argued that if Greece and Turkey did not receive the aid, they would inevitably fall out of the United States' sphere of influence and into the communist bloc, with grave consequences throughout the region.

Containment was a geopolitical strategic foreign policy pursued by the United States during the Cold War to prevent the spread of communism after the end of World War II. The name was loosely related to the term cordon sanitaire, which was containment of the Soviet Union in the interwar period.

Containment represented a middle-ground position between détente (relaxation of relations) and rollback (actively replacing a regime). The basis of the doctrine was articulated in a 1946 cable by U.S. diplomat George F. Kennan during the post-World War II term of U.S. President Harry S. Truman. As a description of U.S. foreign policy, the word originated in a report Kennan submitted to US Defense Secretary James Forrestal in 1947, which was later used in a Foreign Affairs article.

The first island chain is the first string of major Pacific archipelagos out from the East Asian continental mainland coast. It is principally composed of the Kuril Islands, the Japanese archipelago, the Ryukyu Islands, Taiwan (Formosa), the northern Philippines, and Borneo, hence extending all the way from the Kamchatka Peninsula in the northeast to the Malay Peninsula in the southwest. The first island chain forms one of three island chain doctrines within the island chain strategy in the U.S. foreign policy. It is considered a strategic military barrier to accessing the wider Pacific Ocean given the relative shallowness of waters to the west of the first island chain, which has important implications for submarine detection.

Much of the first island chain is roughly situated in waters claimed by the People's Republic of China (PRC). These include the South China Sea, within the disputed nine-dash line, as well as the East China Sea west of the Okinawa Trough.

The island chain strategy is a strategic maritime containment plan first conceived by American foreign policy statesman John Foster Dulles in 1951, during the Korean War. It proposed surrounding the Soviet Union and China with naval bases in the West Pacific to project power and restrict sea access.

The "island chain" concept did not become a major theme in American foreign policy during the Cold War, but after the dissolution of the Soviet Union has remained a major focus of both American and Chinese geopolitical and military analysts to this day. For the United States, the island chain strategy is a significant part of the force projection of the U.S. military in the Far East. For the People's Republic of China (PRC), the concept is integral to its maritime security and fears of strategic encirclement by the U.S. and its allies. For both the U.S. and the PRC, the island chain strategy emphasizes the geographical and strategic importance of Taiwan.