President: Richard Nixon (R-California)
Vice President: Spiro Agnew (R-Maryland)
Chief Justice: Warren E. Burger (Minnesota)
Speaker of the House of Representatives: John William McCormack (D-Massachusetts)
Senate Majority Leader: Mike Mansfield (D-Montana)
January 5 – The first episode of All My Children is broadcast on the ABC television network.
January 11 – Super Bowl IV: The Kansas City Chiefs beat the heavily favored Minnesota Vikings 23–7.
January 14 – Diana Ross & The Supremes perform their farewell live concert together at the Frontier Hotel in Las Vegas, and Ross's replacement, Jean Terrell, is introduced onstage at the end of the last show.
February 17 – MacDonald family massacre: Jeffrey R. MacDonald kills his wife and children at Fort Bragg, North Carolina, claiming that drugged-out "hippies" did it.
February 18 – A jury finds the Chicago Seven defendants not guilty of conspiring to incite a riot, in charges stemming from the violence at the 1968 Democratic National Convention. Five of the defendants are found guilty on the lesser charge of crossing state lines to incite a riot.
March 6 – A bomb constructed by members of the Weathermen and meant to be planted at a military dance in New Jersey explodes, killing 3 members of the organization.
March 17 – My Lai massacre: The United States Army charges 14 officers with suppressing information related to the incident.
March 18 – United States Postal Service workers in New York City go on strike; the strike spreads to the state of California and the cities of Akron, Ohio, Philadelphia, Pennsylvania, Chicago, Boston, and Denver, Colorado; 210,000 out of 750,000 U.S. postal employees walk out. President Nixon assigns military units to New York City post offices. The strike lasts 2 weeks.
March 21 – The first Earth Day proclamation is issued by San Francisco Mayor Joseph Alioto.
March 31 – NASA's Explorer 1, the first American satellite and Explorer program spacecraft, reenters Earth's atmosphere after 12 years in orbit.
President Richard Nixon signs the Public Health Cigarette Smoking Act into law, banning cigarette television advertisements in the United States, starting on January 1, 1971.
American Motors Corporation introduces the Gremlin.
April 10 – Paul McCartney announces that The Beatles are breaking up.
April 11 – Apollo program: Apollo 13 (Jim Lovell, Fred Haise, Jack Swigert) is launched toward the Moon.
April 13 – An oxygen tank in the Apollo 13 spacecraft explodes, forcing the crew to abort the mission and return in 4 days.
April 17 – Apollo program: Apollo 13 splashes down safely in the Pacific.
April 22 – The first Earth Day is celebrated in the U.S.
April 29 – The U.S. invades Cambodia to hunt out the Viet Cong; widespread, large antiwar protests occur in the U.S.
May 1 – Demonstrations against the trial of the New Haven Nine, Bobby Seale, and Ericka Huggins draw 12,000. President Richard Nixon orders U.S. forces to cross into neutral Cambodia, threatening to widen the Vietnam War, sparking nationwide riots and leading to the Kent State Shootings.
May 4 – Kent State shootings: Four students at Kent State University in Ohio are killed and 9 wounded by Ohio State National Guardsmen, at a protest against the incursion into Cambodia.
May 8 – Hard Hat riot: Unionized construction workers attack about 1,000 students and others protesting the Kent State shootings near the intersection of Wall Street and Broad Street and at New York City Hall.
Henry Marrow is killed in an alleged hate crime in Oxford, North Carolina.
Lubbock Tornado: An F5 tornado hits downtown Lubbock, Texas, the first to hit a downtown district of a major city since Topeka, Kansas in 1966; 28 are killed.
May 14 – In the second day of violent demonstrations at Jackson State University in Jackson, Mississippi, state law enforcement officers fire into the demonstrators, killing 2 and injuring 12.
June 6 – A D-Day celebration is held in Washington, D.C..
June 11 – The United States gets its first female generals: Anna Mae Hays and Elizabeth P. Hoisington.
June 22 – U.S. President Richard Nixon signs a measure lowering the voting age to 18. (Voting Rights Act Amendments of 1970)
June 24 – The United States Senate repeals the Gulf of Tonkin Resolution.
June 28 – U.S. ground troops withdraw from Cambodia.
June 30 – Riverfront Stadium in Cincinnati opens.
July 1 – Colorado State College changes its name to University of Northern Colorado.
Bob Hope and other entertainers gather in Washington, D.C. for Honor America Day, a nonpartisan holiday event.
American Top 40, a nationally syndicated radio program featuring a countdown of the top 40 hits of the past week according to the Billboard Hot 100, premieres. Hosted by Casey Kasem, the show is a major success.
July 16 – Three Rivers Stadium in Pittsburgh opens.
July 31 – NBC anchor Chet Huntley retires from full-time broadcasting.
August 7 – Harold Haley, Marin County Superior Court Judge, is taken hostage and murdered, in an effort to free George Jackson from police custody.
August 17 – August 18 – The U.S. sinks 418 containers of nerve gas into the Gulf Stream near the Bahamas.
August 26 – The Women's Strike For Equality takes place down Fifth Avenue in New York City.
August 29 – Rubén Salazar is shot and killed during a rally in East Los Angeles.
September 5 – Vietnam War – Operation Jefferson Glenn: The United States 101st Airborne Division and the South Vietnamese 1st Infantry Division initiate a new operation in Thua Thien Province (the operation ends in October 1971).
September 6 – The Popular Front for the Liberation of Palestine hijacks 4 passenger aircraft from Pan Am, TWA and Swissair on flights to New York from Brussels, Frankfurt and Zürich.
September 7 – An anti-war rally is held at Valley Forge, Pennsylvania, attended by John Kerry, Jane Fonda and Donald Sutherland.
September 9 – Elvis Presley begins his first concert tour since 1958 in Phoenix, Arizona at the Veterans Memorial Coliseum.
September 10 – The Chevrolet Vega is introduced.
September 11 – The Ford Pinto is introduced.
September 13 – The first New York City Marathon begins.
September 18 – Jimi Hendrix dies of alcohol-related complications.
September 26 – The Laguna Fire starts in San Diego County, burning 175,425 acres (710 km²).
September 27 – Richard Nixon begins a tour of Europe, visiting Italy, Yugoslavia, Spain, the United Kingdom and Ireland.
September 29 – The U.S. Congress gives President Richard Nixon authority to sell arms to Israel.
October 2 – The Wichita State University football team's "Gold" plane crashes in Colorado, killing most of the players. They were on their way (along with administrators and fans) to a game with Utah State University.
National Educational Television ends operations, being succeeded by PBS.
In Los Angeles, Rock and blues singer Janis Joplin dies in her hotel room, from an overdose of heroin.
The Public Broadcasting Service begins broadcasting.
U.S. President Richard Nixon's European tour ends.
The U.S. Foreign Office announces that renewal of arms sales to Pakistan.
Vietnam War: In Paris, a Communist delegation rejects U.S. President Richard Nixon's October 7 peace proposal as "a maneuver to deceive world opinion."
October 12 – Vietnam War: U.S. President Richard Nixon announces that the United States will withdraw 40,000 more troops before Christmas.
October 15 – The Baltimore Orioles defeat the Cincinnati Reds in Game 5 of the World Series, 9–3, to win the series 4 games to 1 for their 2nd World Championship.
October 21 – A U.S. Air Force plane makes an emergency landing near Leninakan, Soviet Union. The Soviets release the American officers, including 2 generals, November 10.
October 25 – The wreck of the Confederate submarine Hunley is found off Charleston, South Carolina, by pioneer underwater archaeologist, Dr. E. Lee Spence, then just 22 years old. Hunley was the first submarine in history to sink a ship in warfare.
Garry Trudeau's comic strip Doonesbury debuts in approximately two dozen newspapers in the United States.
Gary Gabelich drives the rocket-powered Blue Flame to an official land speed record at 622.407 mph (1,001.667 km/h) on the dry lake bed of the Bonneville Salt Flats in Utah. The record, the first above 1 000 km/h, stands for nearly 13 years.
November – The 1969–1970 recession ends.
November 3 – Democrats sweep the U.S. Congressional midterm elections; Ronald Reagan is reelected governor of California; Jimmy Carter is elected governor of Georgia.
Vietnam War – Vietnamization: The United States turns control of the air base in the Mekong Delta to South Vietnam.
Social workers in Los Angeles, California take custody of Genie, a girl who had been kept in solitary confinement since her birth.
November 5 – Vietnam War: The United States Military Assistance Command in Vietnam reports the lowest weekly American soldier death toll in 5 years (24 soldiers die that week, which is the fifth consecutive week the death toll is below 50; 431 are reported wounded that week, however).
November 6 - NASA puts a satellite into orbit which it claims can detect missile launching anywhere in the world
November 9 – Vietnam War: The Supreme Court of the United States votes 6–3 not to hear a case by the state of Massachusetts, about the constitutionality of a state law granting Massachusetts residents the right to refuse military service in an undeclared war.
November 10 – Vietnam War – Vietnamization: For the first time in 5 years, an entire week ends with no reports of United States combat fatalities in Southeast Asia.
November 14 – Southern Airlines Flight 932 crashes in Wayne County, West Virginia; all 75 on board, including 37 players and 5 coaches from the Marshall University football team, are killed.
November 17 – Vietnam War: Lieutenant William Calley goes on trial for the My Lai massacre.
November 18 – U.S. President Richard Nixon asks the U.S. Congress for US$155 million in supplemental aid for the Cambodian government (US$85 million is for military assistance to prevent the overthrow of the government of Premier Lon Nol by the Khmer Rouge and North Vietnam).
November 21 – Vietnam War – Operation Ivory Coast: A joint Air Force and Army team raids the Son Tay prison camp in an attempt to free American POWs thought to be held there (no Americans are killed, but the prisoners have already moved to another camp; all U.S. POWs are moved to a handful of central prison complexes as a result of this raid).
November 23 – Rodgers and Hammerstein's Oklahoma! makes its network TV debut, when CBS telecasts the 1955 film version as a 3-hour Thanksgiving special.
December 2 – The United States Environmental Protection Agency begins operations.
December 23 – The North Tower of the World Trade Center is topped out at 1,368 feet (417 m), making it the tallest building in the world.
December 29 – U.S. President Richard Nixon signs into law the Occupational Safety and Health Act.
Cold War (1945–1991)
Space Race (1957–1975)
Vietnam War, U.S. involvement (1962–1973)
Détente (c. 1969–1979)
1970 in the United States Wikipedia
Events from the year 1970 in the United States.