Free The Tunnels of Cu Chi by Tom Mangold

droplets were ignited by gasoline. This system was known as saturation firing: “You didn’t waste any as it shot to the target that way,” said Justen. The diminutive Texan was eventually to specialize in tunnel warfare, but he admits that during Crimp he didn’t quite know what was happening. “We knew nothing about the tunnels, and we had the wrong equipment. Everything that was learned was learned the hard way.”
    Justen used his flame-thrower to burn away jungle and growth near trenches. If this expensive technique exposed a tunnel entrance—some had trapdoors and some did not—then he would explore.
    â€œWe started going down checking tunnels out, and right in the middle of it, while we’re going into one tunnel, they [the VC] would pop up somewhere else and the shooting’d be going on up above you. You could hear them up above ground shooting and you never knew if you popped up out of one of these holes whether somebody from our side might take a shot at you. So you used to tell the guy—in them days we didn’t lay wire or nothing because we were working blind—we used to tell them to hold off if they saw us coming out from a different hole to the one we went in. Hell, you didn’t know where you were going to come out. I went down there, I got real close to Charlie—warm food, papers lying around, even found a calendar with the day’s date on, that’s pretty damn close. But truth is, I’d rather run them out than meet them down there.”
    Justen was later to instruct others in tunnel warfare. He made drawings of what he found, including the tunnel water traps. The water traps, it turned out, were not to deal with drainage. They were rather like U-bends in the tunnel system, and they prevented tear gas or CS riot-control gas from blowing all the way into a tunnel complex. The early tunnel explorers had to navigate the water traps the hard way. Most just waded in, held their breath, and swam up the other side, always assuming they could do it on one lungful of air. “That really was the worst part of me,” explained Justen. “You never knew what was waiting the other side, you never knew if in that black hole you’d get to the other side, and when you did, you cameout soaking wet and stinking rotten. It was the worst part of it.”
    The commander of the 173rd Airborne, Brigadier General Ellis W. Williamson, was to write hugely enthusiastic after-action reports on Operation Crimp. Hindsight gives us all twenty-twenty vision, but history shows some of his optimism to have been either premature or hollow. “Most of January 13th was spent destroying and contaminating the tunnel and bunker system,” he wrote eight days after Crimp had finished. “CS-1, a powder contaminant with long-lasting effects, was used for the first time and should prove quite effective. It was placed throughout the tunnel systems by placing a long line of detonation cord where desired. Crystallized CS-1 was then placed along the detonation cord just prior to the explosion. It is hoped that this approach will prove to be a lasting deterrent.” It was an ill-founded hope. The water traps and the tightly sealed trapdoors connecting the various levels were to ensure that contamination usually failed.
    In
his
after-action report, Colonel William D. Brodbeck of the Big Red One was considerably less sanguine, but more prescient. “CS riot-control agent was used without much success,” he wrote. “Tunnels were baffled by the VC to prevent effective use of CS. Positive results were obtained when men went into the tunnels. A different combat technique is required when a man goes into a tunnel after a VC. However the same amount of courage is required in this type of fighting.”
    As Crimp and Buckskin drew to a close the “Sky Soldiers” remounted their noisy winged horses and flew back to base; the trucks and the APCs ground out