The Beatles sang "I Want to Hold Your Hand," and millions of women in England and America swooned over John, Paul, George and Ringo. Muhammad Ali (still known by his birth name of Cassius Clay) was crowned heavyweight champion of the world and Mary Poppins packed audiences into movie theaters. While Martin Luther King, Jr. was awarded the Nobel Peace Prize, another future Nobel Peace laureate, Nelson Mandela, was sentenced to life in prison in South Africa. Harold Wilson was the prime minister of Britain in 1964, and Lyndon B. Johnson had recently become the president of the United States after the assassination of President Kennedy in Dallas, Texas on November 22, 1963. After a U.S. destroyer was allegedly attacked off the coast of North Vietnam, the U.S. Congress passed the Gulf of Tonkin Resolution, giving Johnson the power to conduct military operations and escalate the war in Vietnam.