According to a recent book, written by a Vietnamese with recently declassified documents, Le Duan (General Secretary of VCP) launched a coup against Ho Chi Minh in 1965, effectively starting the aggressive attempt to unite Vietnam. With the American involvement in 1960 (much earlier), expect the man to remove the idea completely. Ho Chi Minh preferred building up his force in the North (to make it much more self-reliant) before pushing out.