1950-1960 Timeline (: By ClovieKnowles Jun 25, 1950 Korean conflict begins; North Korea invades South Korea Jun 27, 1950 North Korean troops reach Seoul, UN asks members to aid South Korea, Harry Truman orders US Air Force & Navy into Korean conflict Jun 28, 1950 North Korean forces capture Seoul, South Korea in opening phase of the Korean War Jul 3, 1950 1st time US & North Korean forces clash in Korean War Sep 13, 1950 North Korean divisions open assault on UN lines Sep 21, 1950 George Marshall sworn in as the 3rd Secretary of Defense of United States. Feb 27, 1951 22nd amendment ratified, limiting US Presidents to 2 terms Mar 21, 1951 2,900,000 US soldiers in Korea Jan 5, 1952 British Prime Minister Winston Churchill makes an official visit to the US Nov 4, 1952 Dwight Eisenhower is elected president. Jan 7, 1953 US President Harry Truman announces American development of the hydrogen bomb Mar 26, 1953 Dr Jonas Salk announces vaccine to prevent polio Jul 27, 1953 North Korea and South Korea agree to a truce. Feb 2, 1954 President Eisenhower reports detonation of 1st H-bomb Apr 17, 1954 Talks at Geneva fail to unite Korea. Feb 29, 1956 President Eisenhower announces he would seek a 2nd term Mar 24, 1958 Elvis Presley joins the army Mar 26, 1958 US Army launched America's third successful satellite, "Explorer III" Dec 18, 1958 1st voice from space: recorded Christmas message by President Eisenhower May 20, 1959 Japanese-Americans regain their citizenship Jan 19, 1960 Eisenhower & Premier Kishi sign US-Japanese Security pact