brigade could hide down there, but until the Tet Offensive that number was never needed.
Penetration by an aggressor was discouraged. If a vertical shaft was discovered, there could well be a cunning booby trap at the bottom. Firing down the tunnels served no purpose; they changed direction every few yards so a bullet would go straight into the end-wall.
Dynamiting did not work; there were scores of alternate galleries within the pitch-black maze down there, but only a local would know them. Gas did not work; they fitted water seals, like the U-bend in a lavatory pipe.
The network ran under the jungle almost from the suburbs of Saigon nearly to the" Cambodian border. There were various other networks elsewhere but nothing like the Tunnels of Cu Chi, named after the nearest town.
After the monsoon the laterite clay was pliable, easy to dig, scrape back and drag away in baskets. In the dry, it set like concrete.
After the passing of Kennedy, Americans arrived in really significant numbers and no longer as instructors, but for combat, starting spring 1964. They had the numbers, the weapons, the machines, the firepower and they hit nothing. They hit nothing because they found nothing; just an occasional VC corpse if they got lucky. But they took casualties, and the body count began to mount.
At first it was convenient to presume the VC were peasants by day, lost among the black-pyjama-clad millions, switching to guerrillas at night. But why so many casualties by day, and no one to fire back at? In January 1966 the Big Red One decided to raze the Iron Triangle once and for all. It was Operation Crimp.
They started at one end, fanned out and moved forward. They had enough ammunition to wipe out Indochina. They reached the other end and had found no one. From behind the moving line sniper fire started and the GIs took five fatalities. Whoever was firing had only old, bolt-action Soviet carbines, but a bullet through the heart is still a bullet through the heart.
The GIs turned back, went over the same ground. Nothing, no enemy. They took more fatalities, always in the back. They discovered a few foxholes, a brace of air-raid shelters. Empty, offering no cover. More sniper fire but no running figures in black to fire back at.
On Day Four, Sergeant Stewart Green, massively fed up, as were his mates around him, sat for a rest. In two seconds he was up, clutching his butt. Fire ants, scorpions, snakes, Vietnam had them all. He was convinced he had been stung or bitten. But it was a nail-head. The nail was part of a frame, and the frame was the hidden door to a shaft that went straight down into blackness. The US Army had discovered where the snipers went. They had been marching over their heads for two years.
There was no way of fighting the Vietcong living and hiding down there in the darkness by remote control. The society that in three years would send two men to walk on the moon had no technology for the Tunnels of Cu Chi. There was only one way to take the fight to the invisible enemy.
Someone had to strip down to thin cotton pants and, with pistol, knife and torch, go down into that pitch-black, stinking, airless, unknown, unmapped, booby-trapped, deadly, hideously claustrophobic labyrinth of narrow passages with no known exit and kill the waiting Vietcong in their own lair.
A few men were found, a special type of man. Big, burly men were of no use. The 95 per cent who feel claustrophobic were no use. Loud mouths, exhibitionists, look-at-mes were no use. The ones who did it were quiet, soft-spoken, self-effacing, self-contained personalities, often loners in their own units. They had to be very cool, even cold, possessed of icy nerves and almost immune to panic, the real enemy below ground.
Army bureaucracy, never afraid to use ten words where two will do, called them "Tunnel Exploration Personnel'. They called themselves the Tunnel Rats.
By the time Cal Dexter reached Vietnam they had been in existence for three