Polaris ballistic missile for use in the Royal Navy's submarine fleet starting in 1968. The American containment policy called for military resistance to the expansion of communism, and the Vietnam War became the main battlefield in the 1950s down to the communist victory in 1975. Prime Minister Harold Wilson (1964-1970) believed in a strong "Special Relationship" and wanted to highlight his dealings with the White House to strengthen his own prestige as a statesman. President Lyndon B. Johnson disliked Wilson, and ignored any "special" relationship. He agreed to provide financial help but he strongly opposed British plans to devalue the pound and withdraw military units east of Suez. As the American military involvement deepened after 1964, Johnson repeatedly asked for British ground units to validate international support for American intervention. Wilson never sent troops, but British intelligence, training in jungle warfare, and verbal support was provided. He also took the initiative in attempting numerous mediation schemes, typically involving Russian intervention, none of which gained traction. Wilson's policy divided the Labour Party; the Conservative opposition generally supported the American position on Vietnam. Issues of foreign policy were rarely salient in general elections. Wilson and Johnson also differed sharply on British economic weakness and its declining status as a world power. Historian Jonathan Colman concludes it made for the most unsatisfactory "special" relationship in the 20th century. The tone of the relationship was set early on when Johnson sent Secretary of State Dean Rusk as head of the American delegation to the state funeral of Winston Churchill in January 1965, rather than the new vice president, Hubert Humphrey. Johnson himself had been hospitalized with influenza and advised by his doctors against attending the funeral. This perceived slight generated much criticism against the president, both in the UK and in the US. Johnson said during a press conference that not sending Humphrey was a "mistake." 1970s Edward Heath (Prime minister 1970–74) and Richard Nixon (President 1969–74) maintained a close working relationship. Heath deviated from his predecessors by supporting Nixon's decision to bomb Hanoi and Haiphong in Vietnam in April 1972. Nevertheless, relations deteriorated noticeably during the early 1970s. Throughout his premiership, Heath insisted on using the phrase "natural relationship" instead of "special relationship" to refer to Anglo-American relations, acknowledging the historical and cultural similarities but carefully denying anything special beyond that. Heath was determined to restore a measure of equality to Anglo-American relations