Build-up (1960 - 1964) In the late 1950s, a communist guerrilla
force – the Vietcong – emerged in the south. Supported and
supplied from Hanoi via a network of tracks known as the Ho Chi
Minh trail, its ranks were boosted by southerners frustrated
with the corrupt and repressive government of their self-
appointed president, Ngo Dinh Diem. The US had been providing
aid and military equipment and training to south Vietnam since
1954. As the Vietcong grew this was increased, with US
helicopters, armed personnel carriers and thousands of military
advisers on the ground. But by 1963, Diem's government was so
discredited that the US did nothing to stop a coup by dissident
generals. A series of short-lived and unstable governments
followed, proving no more effective against the insurgency. The
catalyst for deeper US involvement came in August 1964, when
north Vietnamese torpedo boats shot at a US destroyer in the
Gulf of Tonkin. US President Lyndon Johnson used a second, and
highly disputed, second clash to justify