''Sam and Friends'' debuts on a local United States television channel, marking the first television appearance of both Jim Henson and what would become Kermit the Frog and The Muppets.

In Operation Redwing (shot ''Cherokee''), the first United States airborne hydrogen bomb is dropped over Bikini Atoll in the Pacific Ocean;

The Federal-Aid Highway Act of 1956 is signed, officially creating the United States Interstate Highway System.

A joint resolution of the U.S. Congress is signed by President Dwight D. Eisenhower, authorizing ''In God We Trust'' as the U.S. national motto.

After going bankrupt in 1955, the American broadcaster DuMont Television Network makes its final broadcast, a boxing match from St. Nicholas Arena in New York in the ''Boxing from St. Nicholas Arena'' series.

The United States and Canada form the North American Air Defense Command (NORAD).

Vietnam War: First United States casualties in Vietnam.

Cold War: The Gaither Report calls for more American missiles and fallout shelters.

Project Vanguard: A launchpad explosion of Vanguard TV3 thwarts the first United States attempt to launch a satellite into Earth orbit.

The United States successfully launches the first Atlas intercontinental ballistic missile at Cape Canaveral, Florida.

Explorer program: ''Explorer 1'' – The first successful launch of an American satellite into orbit.

Samuel Alphonsus Stritch is appointed Pro-Prefect of the Propagation of Faith and thus becomes the first American member of the Roman Curia.

A United States federal court rules that poet Ezra Pound is to be released from an insane asylum.

The John Birch Society was founded in the United States.

The steel strike of 1959 begins, leading to significant importation of foreign steel for the first time in United States history.

First United States Congress elections in Hawaii as a state of the Union.

Nikita Khrushchev becomes the first Soviet leader to visit the United States.

Belgium defends its intervention in the Congo to the United Nations Security Council while the government of the Congo appeals to the Soviet Union to send troops to push back the Belgians. The governments of the United States and France and the North Atlantic Treaty Organization warn the Soviets to stay out of the dispute.

Cuban Revolution: in response to a United States embargo, Cuba nationalizes American and foreign-owned property in the nation.

Sabena Flight 548 crashes in Belgium, killing 73, including the entire United States figure skating team, several coaches and family.

United States President John F. Kennedy sends 18,000 military advisors to South Vietnam.

The United States bans all Cuban imports and exports.

Captured American U2 spy-plane pilot Gary Powers is exchanged for captured Soviet spy Rudolf Abel.

The Old Bay Line, the last overnight steamboat service in the United States, goes out of business.

Cuban Missile Crisis between the United States and Cuba begins.

Travel, financial and commercial transactions by United States citizens to Cuba are made illegal by the John F. Kennedy administration.

The United States, the United Kingdom, and the Soviet Union sign a nuclear test ban treaty.

The Hotline between the leaders of the U.S.A. and the Soviet Union goes into operation.

''CBS Evening News'' becomes U.S. network television's first half-hour weeknight news broadcast, when the show is lengthened from 15 to 30 minutes.

The 16th Street Baptist Church bombing: Four children killed at an African-American church in Birmingham, Alabama, United States

Vietnam War: Newly sworn-in US President Lyndon B. Johnson confirms that the United States intends to continue supporting South Vietnam both militarily and economically.

U.S. President Lyndon B. Johnson announces the goals of his Great Society social reforms to bring an "end to poverty and racial injustice" in America.

Vietnam War: 5,000 more American military advisers are sent to South Vietnam bringing the total number of United States forces in Vietnam to 21,000.

Gulf of Tonkin Incident: U.S. destroyers USS Maddox and USS Turner Joy report coming under attack in the Gulf of Tonkin.

Vietnam War: the U.S. Congress passes the Gulf of Tonkin Resolution giving US President Lyndon B. Johnson broad war powers to deal with North Vietnamese attacks on American forces.

Cold War: Indian Prime Minister Jawaharlal Nehru appeals to the United States and the Soviet Union to end nuclear testing and to start nuclear disarmament, stating that such an action would "save humanity from the ultimate disaster".

Vietnam War: The first United States combat troops are sent to South Vietnam.

NASA launches Gemini 3, the United States' first two-man space flight (crew: Gus Grissom and John Young).

Vietnam War: The United States uses B-52 bombers to attack National Liberation Front guerrilla fighters in South Vietnam.

Cuba and the United States formally agree to begin an airlift for Cubans who want to go to the United States. By 1971, 250,000 Cubans made use of this program.