By Will Mears
Two recent Veterans Breakfast Club programs have featured veterans of the Army Security Agency (ASA) whose work was important and behind-the-scenes. Their job was, among other things, to intercept, decode, and interpret enemy communications in real time. It was painstaking, highly technical work, carried out under strict secrecy. And yet, as many ASA veterans will tell you, what they heard could mean the difference between life and death for American troops in the field.
You can watch two of our recent ASA programs here:
https://www.youtube.com/live/62cEr2h9iy4?si=LVhIHQA4Q2T5AhwQ
https://www.youtube.com/watch?v=T9KvZg6kqlY
Will Mears was one of the veterans who joined our conversations. Will served in the U.S. Army Security Agency from 1965 to 1969 as a Morse interceptor (MOS 05H) with Top Secret cryptographic clearance. He trained at Fort Devens and served at ASA field stations in Japan and Vietnam, including the 8th Radio Research Field Station at Phu Bai. There, he worked in signals intelligence (SIGINT/COMINT), tracking enemy communications across Vietnam and Laos, often in direct support of Marine units and MACV-SOG operations.
What follows is Mears’s account of a moment in late 1967, when ASA intelligence intersected directly with one of the most consequential battles of the Vietnam War: Khe Sanh.
In a recent Veterans Breakfast Club conversation, someone asked how many American lives were saved by the work of the Army Security Agency.
No one can say for sure. But one moment from late 1967 offers a glimpse.
At the 8th Radio Research Field Station at Phu Bai, a small group of Morse intercept operators—including myself—were asked to attend a briefing for General William Westmoreland. We were between monitoring assignments and able to step away. There were six of us.
Westmoreland arrived just before 7 p.m., accompanied by his adjutant. The briefing focused on intelligence we had been gathering through intercepted North Vietnamese communications.
We had identified the movement of two North Vietnamese Army (NVA) divisions—roughly 10,000 troops each—positioning themselves one to two miles northwest of Khe Sanh. Behind them, another two divisions were moving into place, four to five miles back, clearly intended as reinforcements.
The implication was unmistakable: the enemy was preparing to overrun Khe Sanh.
At the time, American and allied forces at Khe Sanh were limited—about 5,000 Marines from the 26th Marine Regiment, roughly 400 ARVN Rangers, and a small number of MACV-SOG personnel and Montagnard fighters. Reinforcements were difficult to shift without weakening other positions across I Corps.
We briefed General Westmoreland on what we were seeing and recommended reinforcing Khe Sanh.
He added approximately 500 Marines to the base.
At the end of the briefing, Westmoreland turned to us and said:
“Thank you for all that you are doing. If someone told me you had saved the lives of 10,000 of our troops, I would not dispute that. Thank you.”
As we saluted, I said, “Sir, if we saved only one soldier, it was worth it.”
Westmoreland smiled, then left the room.
In the months that followed, the two NVA divisions positioned near Khe Sanh suffered devastating losses—estimated at around 15,000 casualties—and were effectively destroyed. The reserve divisions were pulled back into Laos.
No one will ever know how many lives were saved by the intelligence gathered in places like Phu Bai.
