1913 – The formal charter of the Marine Corps Association was established.
1914 – First combat observation mission by Navy plane, at Veracruz, Mexico.
1943 – American bombers raid an airfield around Bari, Italy in the south.
1945 – Elbe Day: United States and Soviet troops meet in Torgau along the River Elbe, cutting the Wehrmacht of Nazi Germany in two, a milestone in the approaching end of World War II in Europe.
1945 – Liberation Day (Italy): The Nazi occupation army surrenders and leaves Northern Italy after a general partisan insurrection by the Italian resistance movement. The puppet fascist regime dissolves and Benito Mussolini is captured after trying to escape. This day was set as a public holiday to celebrate the Liberation of Italy.
1945 – Delegates from some 50 countries met in San Francisco to organize the United Nations. Charles Easton Rothwell (d.1987) headed the 500-member group that helped establish the UN Charter.
1945 – Soviet forces complete the encirclement of Berlin near Ketzin. The 1st Belorussian and 1st Ukrainian froms continue to attack, from the east and south, into the city. South of the capital, elements of 1st Ukrainian Front advancing toward the Elbe River, link up with American units at Torgau. Meanwhile, in East Prussia, Pillau is taken. (Since early in the year, about 140,000 wounded and 40,000 refugees have been evacuated to the west from Pillau.) A few German troops continue to hold out at the tip of the Samland Peninsula. US 3rd Army crosses the Danube near Regensburg and assault the city.
1945 – American planes strike Pilsen, Czechoslovakia, nominally the Skoda Works.
1945 – Clandestine Radio 1212, used to hoax Nazi Germany, made its final transmission.
1951 – Eighth Army was pushed back 20 miles. The volunteer battalion from Belgium and Luxembourg was cut off but fought its way to safety after a 20-hour siege. Members of the battalion had high praise for the support provided by U.S. Marine Corsairs.
1953 – 1953 – Francis Crick and James D. Watson publish “Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” describing the double helix structure of DNA.
1954 – The first practical solar cell is publicly demonstrated by Bell Telephone Laboratories.
1954 – UK Prime Minister Winston Churchill rejects the US proposed Radford Plan, initially conceived of as a nuclear strike but negotiated down to a massive US air strike against the Viet Minh in response to the fall of Dienbienphu. Churchill states, “What we are being asked to do is assist in misleading the Congress into approving a military operation which would be in itself ineffective, and might well bring the world to the verge of a major war.”
1957 – The 1st experimental sodium nuclear reactor operated.
1960 – First submerged circumnavigation of the Earth was completed by a Triton submarine. Operation Sandblast was the code name for the first submerged circumnavigation of the world executed by the United States Navy nuclear-powered radar picket submarine USS Triton (SSRN-586) in 1960 while under the command of Captain Edward L. Beach, USN. The New York Times described Triton ’s submerged circumnavigation of the Earth as “a triumph of human prowess and engineering skill, a feat which the United States Navy can rank as one of its bright victories in man’s ultimate conquest of the seas.” The actual circumnavigation took place between 24 February and 25 April 1960, covering 26,723 nautical miles (49,491 km; 30,752 mi) over 60 days and 21 hours. Operation Sandblast used the St. Peter and Paul Rocks, located in the middle of the Atlantic Ocean near the Equator, as the starting point and terminus for the circumnavigation. During the course of the circumnavigation, Triton crossed the Equator four times while maintaining an average speed of advance (SOA) of 18 knots (33 km/h; 21 mph). Triton ’s overall navigational track during Operation Sandblast generally followed the same course for the first circumnavigation of the world led by Portuguese explorer Ferdinand Magellan between 1519-1522. The initial impetus for Operation Sandblast was to enhance American technological and scientific prestige prior to the May 1960 Paris Summit between U.S. President Dwight D. Eisenhower and Soviet Premier Nikita Khrushchev. Additionally, Operation Sandblast provided a high-profile public demonstration of the capability of U.S. Navy nuclear-powered submarines to carry out long-range submerged operations independent of external support and undetected by hostile forces, presaging the initial deployment of the U.S Navy’s Polaris ballistic missile submarines later in 1960. Finally, Operation Sandblast gathered extensive oceanographic, hydrographic, gravimetric, geophysical, and psychological data during Triton ’s circumnavigation. Although official celebrations for Operation Sandblast were cancelled following the diplomatic furor arising from the shooting down of a CIA U-2 spy plane over the Soviet Union in early May 1960, the Triton did receive the Presidential Unit Citation with a special clasp in the form of a golden replica of the globe in recognition of the successful completion of its mission, and Captain Beach received the Legion of Merit for his role as Triton ’s commanding officer. In 1961, Beach received the Magellanic Premium, the United States’ oldest and most prestigious scientific award, from the American Philosophical Society in “recognition of his navigation of the U.S. submarine Triton around the globe.”
1961 – Robert Noyce patented the integrated circuit.
1961 – Mercury-Atlas rocket lifted off with an electronic mannequin. An unmanned Mercury test exploded on launch pad.
1962 – U.S. Ranger spacecraft crash landed on the Moon.
1964 – President Lyndon B. Johnson announces that Gen. William Westmoreland will replace Gen. Paul Harkins as head of U.S. Military Assistance Command Vietnam (MACV) as of June 20. The assignment would put Westmoreland in charge of all American military forces in Vietnam. One of the war’s most controversial figures, General Westmoreland was given many honors when the fighting was going well, but when the war turned sour, many Americans saw him as a cause of U.S. problems in Vietnam. Negative feeling about Westmoreland grew particularly strong following the Tet Offensive of 1968, when he had requested a large number of additional troops for deployment to Vietnam. On March 22, 1968, President Johnson announced that Westmoreland would depart South Vietnam to take on the post of Army Chief of Staff; Gen. Creighton Abrams replaced him as the senior U.S. commander in South Vietnam.
1972 – Hanoi’s 320th Division drives 5,000 South Vietnamese troops into retreat and traps about 2,500 others in a border outpost northwest of Kontum in the Central Highlands. This was part of the ongoing North Vietnamese Nguyen Hue Offensive, also known as the “Easter Offensive,” which included an invasion by 120,000 North Vietnamese troops. The offensive was based on three objectives: Quang Tri in the north, Kontum in the Central Highlands, and An Loc in the south–just 65 miles north of Saigon. If successful, the attack at Kontum would effectively cut South Vietnam in two across the Central Highlands, giving North Vietnam control of the northern half of South Vietnam. The South Vietnamese defenders were able to hold out and prevent this from happening.
1975 – Fearing impending coup, President Thieu flees Saigon following his resignation and transfer of authority to Vice President Tran Van Huong.
1976 – All-Vietnam elections are held for a new National Assembly. 249 deputies are elected from the North and 243 from the South with 6 seats of the total 492 reserved for minorities.
1980 – President Jimmy Carter announced the hostage rescue disaster in Iran.
1982 – In accordance with Camp David agreements, Israel completed the Sinai withdrawal. Ariel Sharon, as defense minister, directed the dismantling of Israeli settlements in the Sinai Peninsula. Nearly 5,000 residents and many more sympathizers were dragged off roofs and bundled onto buses.
1983 – The Pioneer 10 spacecraft crossed Pluto’s orbit, speeding on its endless voyage through the Milky Way.
1988 – NASA launched space vehicle S-211.
1990 – The crew of the U.S. space shuttle Discovery places the Hubble Space Telescope, a long-term space-based observatory, into a low orbit around Earth. The space telescope, conceived in the 1940s, designed in the 1970s, and built in the 1980s, was designed to give astronomers an unparalleled view of the solar system, the galaxy, and the universe. Initially, Hubble’s operators suffered a setback when a lens aberration was discovered, but a repair mission by space-walking astronauts in December 1993 successfully fixed the problem, and Hubble began sending back its first breathtaking images of the universe. Free of atmospheric distortions, Hubble has a resolution 10 times that of ground-based observatories. About the size of a bus, the telescope is solar-powered and orbits Earth once every 97 minutes. Among its many astronomical achievements, Hubble has been used to record a comet’s collision with Jupiter, provide a direct look at the surface of Pluto, view distant galaxies, gas clouds, and black holes, and see billions of years into the universe’s past.
1991 – The White House threatened to “take whatever steps are necessary” should Iraq fail to meet a deadline for withdrawing its security forces from the refugee zone in northern Iraq.
1999 – On the third and final day of their Washington summit, NATO leaders promised military protection and economic aid to Yugoslavia’s neighbors for standing with the West against Slobodan Milosevic. Pres. Yeltsin called Pres. Clinton to search for a solution to Kosovo.
1999 – NATO airstrikes in Yugoslavia destroyed the last bridge in Novi Sad along with other targets in northern and central Serbia. The KLA staged a new conference in Kukes and pleaded anew for a battlefield alliance with NATO.
1999 – In Iraq US warplanes struck air defense sites in the northern no fly zone after being threatened by radar.
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