Special-ops units from Down Under made their mark with US commandos in Vietnam. They may have to do it again against China.

• During the Vietnam War, US troops were supported by forces from several allied countries.
• Australia and New Zealand sent special-operations troops to fight alongside US commandos.

Although the Vietnam War is remembered as a US war, US allies, including Australia and New Zealand, sent troops to fight there as well.

The role of the Australian Special Air Service Regiment (SASR) and the New Zealand Special Air Service (NZSAS) was especially notable. From 1966 to 1971, these two special-operations units deployed a small number of commandos to support conventional forces in Vietnam.

At first, the two units gathered intelligence for the conventional forces through long-range reconnaissance patrols. Gradually, however, they shifted to a more aggressive stance and started going after high-value North Vietnamese and Viet Cong targets in ambushes and direct-action operations.

Australian and Kiwi special operators quickly earned a fearsome reputation. They conducted about 1,400 operations and accounted for more than 500 North Vietnamese and Viet Cong killed or captured, while losing only two men.

Their professionalism and unmatched bushcraft led the North Vietnamese to nickname them "Ma Rung," or "phantoms of the jungle."

To this day, the Australian and Kiwi commandos' patrolling and tracking skills are highly regarded, and they could again be quite effective in a conflict with China.

Hunting in the jungle

The jungle was a familiar hunting ground for the Australian and New Zealand commandos.

Special operators from the two countries had fought with the British against Communist insurgents in Malaya and Borneo. They gained institutional knowledge of patrolling and bushcraft during these conflicts, which enabled their devastating success in Vietnam.

In Vietnam, SASR and NZSAS patrols, composed of four to six commandos, carried a lot more firepower than was the norm in order to appear to be a larger force if they bumped into the North Vietnamese. Rifles, grenades and grenade launchers, machine guns, anti-personnel mines, and other explosives were their staples.

But wielding firepower is a common skill, and it was bushcraft skills that ensured the survival of SASR and NZSAS commandos in Vietnam. Few troops can take the physical and mental beating required in intelligence-gathering operations in dense jungle and surrounded by thousands of enemies.

"The hardest aspect for me was trying to be constantly vigilant as, believe it or not, the enemy, either NVA or Viet Cong, seemed to be everywhere!" Sam McDonald, a former SASR operator who served in Vietnam, told Insider.

Jungle operations were physically demanding. Often, the operators would need the better part of a day just to cover 100 to 200 meters.

Their snail-like pace was necessary to remain undetected. Snapping dead tree branches, splashing puddles of water, rustling blades of grass, and disturbing soil were all things that could give away their position to a highly skilled tracker.

The North Vietnamese used special tactics, including dogs, and their fearsome "sappers" — a special-operations unit developed to counter US, Australian, and New Zealand special operators — to search for patrols operating behind their lines.

The mental toll was even heavier. Once on the ground, teams had to operate in silence.

"Imagine four or five people sitting there for up to five days, not moving, not being able to cook or heat water for a drink or cook their food, eating cold food, and having enemy activity as close as 10 feet away from you. There's a lot of cold sweats, there's a lot of hot sweats," a former NZSAS operator said in a 2007 documentary about the unit.

While they were on patrol, the operators would use hand signals to communicate. If they had to check in with an airborne forward observer, they would just click the radio handset to pass a message. Under such conditions, they got to know each other better than their own siblings and could often anticipate the move of another patrol member just by looking at them.

Every part of their missions were fraught with danger, even on the way out.

In one instance, exhausted NZSAS commandos were patrolling back to their base after an eight-day jungle reconnaissance mission when they stumbled upon the enemy. "We heard these Vietnamese voices yapping. I said, 'Jesus what's that?' A guy said 'Charlie,'" a former NZSAS trooper said.

The Kiwi commandos stayed low, hoping that the enemy would pass without noticing them. But a couple of North Vietnamese sensed something and left the trail to investigate. The NZSAS patrol mowed them down.

Old lessons for a future war

Both units held onto the knowledge they picked up in Vietnam. "Upon my return to Perth, I was put on the staff of the SAS selection course to pass on knowledge of Vietnam," McDonald said.

To this day, NSZAS veterans of Vietnam will test and provide feedback to new troopers who are going through the patrolling phase of the NZSAS selection.

If current tensions with China in the Indo-Pacific region escalate into a full-blown war, special-operations troops from the US and allied militaries could find themselves busy conducting reconnaissance of military installations, such as airbases and missiles sites, in the region — and potentially in mainland China — to gather intelligence and targeting data for precision strikes.

While technological advances have transformed the battlefield, in the unique and unforgiving jungle environment many "analog" practices are still valuable. Re-embracing the bushcraft developed in the jungles of Vietnam could prove critical for such operations, especially after 20 years fighting in open desert terrain against lightly armed opponents.

"The jungle is a very unforgiving environment," a US Air Force special operator said during jungle-warfare training in Hawaii this spring. "Everything is so different, so we need to get used to that kind of environment to be effective."

Stavros Atlamazoglou is a defense journalist specializing in special operations, a Hellenic Army veteran (national service with the 575th Marine Battalion and Army HQ), and a Johns Hopkins University graduate. He is currently working toward a master's degree in strategy and cybersecurity at the Johns Hopkins School of Advanced International Studies.