BOOBY TRAPS WESTERN PERIMETER

Nui Ba Den had a body count before I ever set foot on it.

In 1968, the Viet Cong walked into the compound like they owned it. Blew the signal equipment to scrap. Killed anyone they found standing. No fight worth the name — just complacency meeting a determined enemy, and complacency lost. That was the mountain I inherited as executive officer.

I was not going to preside over a repeat.

Harry Meyers made it possible. Our First Sergeant — career infantry, the kind of soldier who’d forgotten more about defending a perimeter than most officers ever learn — and he backed my plan from the first sketch. Together we set out to build a perimeter that exceeded Army standard, because Army standard was what got the last garrison killed.

Our enemy had beaten better defenses than ours. They’d fought the Japanese. They’d fought the French. Fixed positions were not a mystery to them — they were a specialty.

We started with a survey. Eighteen bunkers, charted in order, graded on how fast an enemy could kill the men inside.

Fifteen of them were sound. Steep ground, clear fields of fire — anything coming at them would die in the open. Bunkers 5, 6, and 7 were the exception. A boulder field sat in front of them, house-sized rocks scattered across the slope, and every boulder was a free pass for a Viet Cong soldier to move closer without being seen. From 5, 6, and 7, you couldn’t see your own death coming.

I couldn’t make the boulders disappear. What I could do was make sure whatever got through them didn’t survive to reach the wire — and that meant slowing the attack down long enough for my Reaction Force to close the gap and finish it.

Harry and I spent hundreds of hours on that western slope, walking it as if we were the enemy, hunting for the paths a man could take through the rocks without ever showing himself. We found plenty. We found no way to close all of them. I was ready to call it an unsolvable problem when I thought of the Ho Chi Minh Trail — and the sensors we used to track movement on it.

It was a long shot. I wrote to my brigade intelligence officer and made the case. A week later, six sensors showed up, along with instructions that only I was cleared to operate them, and any that survived the deployment were to be returned to brigade when I was done.

I placed them in front of bunkers 3 through 8 and started monitoring. The receiver had to go on the tower over the pagoda — the highest point on the mountain, close to forty feet of exposed lumber — and every night, eleven to three, I climbed it and read the signals.

Two weeks in, the picture was clear. Bunkers 6 and 7 were being probed, over and over, while the rest of the line stayed quiet. The enemy had already picked their route. Now I knew it too.

We went to work on the western perimeter like the mountain owed us something. A third row of triple concertina went up along the outer wire, and we killed every scrap of vegetation with herbicide so nothing could hide a man on his belly. Then came the tanglefoot — so much of it that our own soldiers refused to walk the field in daylight, let alone at night.

Behind bunkers 5 and 7, fifty feet back, we built two camouflaged positions and dropped a .50-caliber machine gun in each, sited to rake the bunker line if it ever came to that. Last-stand weapons. Covered by day, forgotten by anyone who didn’t need to know they were there. I never asked permission to build them. I mentioned it to Major Campbell, once, in passing. The guns and their placement were mine to answer for.

Meyers had his mortar teams plot fire in front of all three weak bunkers and passed the coordinates to two fire bases lower on the mountain, so if the line broke, the whole hillside could answer for it.

I kept reading the sensors through April, and by the start of May I wanted to do more than watch. A couple of times a week, the mortars would drop two or three 81mm rounds in front of the bunkers at random hours — harassment fire, nothing that ever drew blood, but enough to remind whoever was out there that we knew they were coming.

I wanted something with teeth. I requisitioned two M-3A1 shaped charges from the Army Engineers — bunker-busters, meant for concrete and steel, not boulders and men — and rigged them to command-detonate from bunker 6. We laid them fifty feet apart, on their sides, coiled barbed wire stacked in front of each one to turn the blast into shrapnel, then buried the whole arrangement under brush until it looked like nothing at all. Ten Claymores wired together, more or less. Just louder.

We waited for the sensors to light up, and one night they did. I gave the order from the tower. Both charges went off five seconds apart, and the sky over that slope turned white. I felt the concussion through the tower legs, forty feet up, a long way from the blast.

The patrol went out at first light. Blood trails everywhere across the kill zone — dragged through the dirt, pooled where someone had stopped moving and started again — but no bodies. They’d carried their dead off in the dark, the way they always did.

The sensors stayed quiet after that. Two full weeks, nothing. I called it a win and moved on to the next problem.

They didn’t come back to that stretch of wire until June 16th, 1969.

When the attack finally came, bunker 7 was the first position the Viet Cong took down.

All those months. The sensors, the tower, the wire, the charges, the guns nobody knew about — and the mountain still took the bunker I’d worried over most. That’s the arithmetic of Nui Ba Den. You buy time. You don’t buy certainty. The Viet Cong held ninety-five percent of that mountain the whole time I was on it, and every improvement I made to the perimeter was really just one more argument for why the other five percent should stay ours a little longer.

Kill or be killed was not a figure of speech up there. It was the only rule that mattered.