The tunnels of Cu Chi were built over a period of 25 years that began sometime in the late 1940s. They were the improvised response of a poorly equipped peasant army to its enemy’s high-tech ordnance, helicopters, artillery, bombers and chemical weapons.
The Viet Minh built the first dugouts and tunnels in the hard, red earth of Cu Chi (ideal for their construction) during the war against the French. The excavations were used mostly for communication between villages and to evade French army sweeps of the area.
When the VC’s National Liberation Front (NLF) insurgency began in earnest around 1960, the old Viet Minh tunnels were repaired and new extensions were excavated. Within a few years the tunnel system assumed enormous strategic importance, and most of Cu Chi district and the nearby area came under firm VC control. In addition Cu Chi was used as a base for infiltrating intelligence agents and sabotage teams into Saigon. The stunning attacks in the South Vietnamese capital during the 1968 Tet Offensive were planned and launched from Cu Chi.
In early 1963 the Diem government implemented the botched Strategic Hamlets Program, under which fortified encampments, surrounded by many rows of sharp bamboo spikes, were built to house people who had been ‘relocated’ from communist-controlled areas. The first strategic hamlet was in Ben Cat district, next to Cu Chi. Not only was the programme carried out with incredible incompetence, alienating the peasantry, but the VC launched a major effort to defeat it. The VC were able to tunnel into the hamlets and control them from within. By the end of 1963 the first showpiece hamlet had been overrun.
The series of setbacks and defeats suffered by the South Vietnamese forces in the Cu Chi area rendered a complete VC victory by the end of 1965 a distinct possibility. In the early months of that year, the guerrillas boldly held a victory parade in the middle of Cu Chi town. VC strength in and around Cu Chi was one of the reasons the Johnson administration decided to involve US troops in the war.
To deal with the threat posed by VC control of an area so near the South Vietnamese capital, one of the USA’s first actions was to establish a large base camp in Cu Chi district. Unknowingly, they built it right on top of an existing tunnel network. It took months for the 25th Division to figure out why they kept getting shot at in their tents at night.
The US and Australian troops tried a variety of methods to ‘pacify’ the area around Cu Chi, which came to be known as the Iron Triangle. They launched large-scale ground operations involving tens of thousands of troops but failed to locate the tunnels. To deny the VC cover and supplies, rice paddies were defoliated, huge swathes of jungle bulldozed, and villages evacuated and razed. The Americans also sprayed chemical defoliants on the area aerially and a few months later ignited the tinder-dry vegetation with gasoline and napalm. But the intense heat interacted with the wet tropical air in such a way as to create cloudbursts that extinguished the fires. The VC remained safe and sound in their tunnels.
Unable to win this battle with chemicals, the US army began sending men down into the tunnels. These ‘tunnel rats’, who were often involved in underground fire fights, sustained appallingly high casualty rates.
When the Americans began using German shepherd dogs, trained to use their keen sense of smell to locate trapdoors and guerrillas, the VC began washing with American soap, which gave off a scent the canines identified as friendly. Captured US uniforms were put out to confuse the dogs further. Most importantly, the dogs were not able to spot booby traps. So many dogs were killed or maimed that their horrified handlers then refused to send them into the tunnels.
The USA declared Cu Chi a free-strike zone: little authorisation was needed to shoot at anything in the area, random artillery was fired into the area at night, and pilots were told to drop unused bombs and napalm there before returning to base. But the VC stayed put. Finally, in the late 1960s, American B-52s carpet-bombed the whole area, destroying most of the tunnels along with everything else around. The gesture was militarily useless by then because the USA was already on its way out of the war. The tunnels had served their purpose.
The VC guerrillas serving in the tunnels lived in extremely difficult conditions and suffered horrific casualties. Only about 6000 of the 16, 000 cadres who fought in the tunnels survived the war. Thousands of civilians in the area were killed. Their tenacity was extraordinary considering the bombings, the pressures of living underground for weeks or months at a time and the deaths of countless friends and comrades.
The villages of Cu Chi have since been presented with numerous honorific awards, decorations and citations by the government, and many have been declared ‘heroic villages’. Since 1975 new hamlets have been established and the population of the area has more than doubled; however, chemical defoliants remain in the soil and water, and crop yields are still poor.
The Tunnels of Cu Chi, by Tom Mangold and John Penycate, is a wonderful work documenting the story of the tunnels and the people involved on both sides.