As a mathematics and political science student at the elite Saigon University in the early 1960s, Nguyen Minh Triet, the son of a farming family, was caught up in the leftist student movement, joining – in the words of his official biography – “the revolutionary base”.

For a decade after his graduation, Mr Triet was an activist in southern Vietnam with the Communist party’s youth movement, an organisation that drummed up popular support for the communist resistance to the US-backed Saigon regime. He was also sent to the battlefield in My Tho province, the site of heavy fighting between US-backed forces and Viet Cong guerrillas.