<P> Similarly, historian Arthur Schlesinger Jr. states that "it was not until September, 1960 that the Communist Party of North Vietnam bestowed its formal blessing and called for the liberation of the south from American imperialism". </P> <P> By contrast, James Olson and Randy Roberts assert that North Vietnam authorized a low - level insurgency in December 1956 . To counter the accusation that North Vietnam was violating the Geneva Accord, the independence of the Viet Cong was stressed in communist propaganda . </P> <P> In March 1956, southern communist leader Lê Duẩn presented a plan to revive the insurgency entitled "The Road to the South" to the other members of the Politburo in Hanoi, but as both China and the Soviets opposed confrontation at this time, Lê Duẩn's plan was rejected . However the North Vietnamese leadership approved tentative measures to revive the southern insurgency in December 1956 . Communist forces were under a single command structure set up in 1958 . The North Vietnamese Communist Party approved a "people's war" on the South at a session in January 1959 and in May, Group 559 was established to maintain and upgrade the Ho Chi Minh trail, at this time a six - month mountain trek through Laos . About 500 of the "regroupees" of 1954 were sent south on the trail during its first year of operation . The first arms delivery via the trail was completed in August 1959 . About 40,000 communist soldiers infiltrated into the south from 1961--63 . </P> <P> In the 1960 U.S. presidential election, Senator John F. Kennedy defeated incumbent Vice President Richard Nixon . Although Eisenhower warned Kennedy about Laos and Vietnam, Europe and Latin America "loomed larger than Asia on his sights ." In his inaugural address, Kennedy made the ambitious pledge to "pay any price, bear any burden, meet any hardship, support any friend, oppose any foe, in order to assure the survival and success of liberty ." In June 1961, he bitterly disagreed with Soviet premier Nikita Khrushchev when they met in Vienna to discuss key U.S.--Soviet issues . Only 16 months later, the Cuban Missile Crisis (16--28 October 1962) played out on television worldwide . It was the closest the Cold War came to escalating into a full - scale nuclear war, and the U.S. raised the readiness level of Strategic Air Command (SAC) forces to DEFCON 2 . </P>

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