Several times early in this blog I referred to “the Cassandra Effect.” That’s the term I coined for the dilemma I faced repeatedly in Vietnam: foretelling what the enemy was going to do and not being believed.
My job in Vietnam was signals intelligence, the intercept and exploitation of the radio communications of the invading North Vietnamese. As noted several times in this blog, between 1962 and 1975, I was in Vietnam at least four months each year. I had two complete tours there and so many shorter trips I lost count. I worked with U.S. military forces, both army and Marines, in combat all over South Vietnam.
I knew North Vietnamese radio communications like the back of my hand. I’d been intercepting and exploiting them since 1960. I spoke Vietnamese, Chinese, and French (the three languages of Vietnam), and I knew what changes the North Vietnamese introduced into their communications as they prepared for combat.
Hence, I was able to foretell the enemy’s attacks by watching his communications. As the North Vietnamese prepared for combat, they followed an established pattern: command elements moved in, reconnaissance began, combat forces took their positions, a simplified signal plan was introduced for ease of communication during combat, and a forward HQ—a tactical command post—took control of fighting units.
I saw the pattern so many times that my senses were tuned to watching for them. What I wasn’t prepared for was the failure of U.S. Army commanders to believe my warning and act on it. Again and again I warned and was ignored. Disaster often followed.
As I said earlier in this blog, Cassandra and I were siblings. We were both blessed with the ability to foretell the future and cursed with disbelief. It happened to me repeatedly. Most famously U.S. Army officers failed to heed my warning at the 1967 battle of Dak To and before the 1968 Tet Offensive. But American civilians were not immune to disbelief. I alerted the U.S. ambassador in April 1975 that the North Vietnamese were preparing to attack Saigon. He didn’t believe me and forbade me to evacuate my subordinates. I did anyway, then escaped under fire after the North Vietnamese were already in the streets of the city.