Peter Braestrup was an American journalist who served as a correspondent in Vietnam. Here he comments on the South Vietnamese military and its problems and weaknesses:

“In 1972, the South Vietnamese army did a fine job of repulsing the North Vietnamese Easter offensive. I was running around in the field with U.S. marine advisors. And I saw that the glue for the South Vietnamese dual-command structure, say where the generals of the South Vietnamese marines and airborne wouldn’t talk to each other, was the U.S. advisers. The U.S. marine advisor and the U.S. airborne advisor would talk and get the job done.

Without the advisors present, it would have been chaos. They were the reinforcing rods in the cement. Partly because of the American firepower and logistics they could bring in. But just as much because they supplied the vertebrae and command structure — the teamwork notion — that the South Vietnamese, because of their fragmented society and history, had not developed. Oppositely, the North Vietnamese in 1972 had one command focus, concentration, abundant supplies. The vertebrae were much stronger with the totalitarians, who had an enforced, unified structure.

From 1971 to 1973, our logistics, airpower, and advisors — those three elements — offset the long-term strategic advantage of the North Vietnamese, which was the sanctuaries in Laos and Cambodia and the Ho Chi Minh Trail. If Laos and Cambodia had been truly neutral, there’s no way that the South Vietnamese, with a little advisory help, couldn’t have held on indefinitely. It was the geography. Even had the South Vietnamese army been the Israeli army, supplied the same way and with the same kind of leadership, the geography would have killed them.

With that six-hundred-mile frontier where the Communists had a free shot at South Vietnam, a safe place to retreat to, and a secure supply line on the Ho Chi Minh Trail, there was no way the South could hold. The geography was against them. And of course, Lyndon Johnson and Richard Nixon preferred to make us all think about the war as if South Vietnam was an island.”