Surviving the Vietnamese tunnels

During the 1950s, Vietnam was a very politically unstable country and was divided into two major factions, the communist north and the democratic south. On 1 November 1955, a conflict broke out between the two sides and this led to a proxy war being fought in the country. Various communist nations supported the northern forces and Anti-communist nations supported the south, with the biggest contributor being the United States.

(One of the Củ Chi tunnels in Vietnam available for tours)

On 8 March 1965, The US sent in its first ground forces to establish bases in the country to help the southern forces take the country and stop the spread of communism. The American forces had much more advanced weaponry and tactics, and this led to the Northern forces trying to avoid large, open-field battles with them. The Americans had both artillery and a large number of planes in the area, dropping such horrific weapons as napalm.

The Northern forces, also known as the Vietcong had no way of meeting the American threat head-on and instead resorted to using guerilla tactics to strike back. These took the form of primitive but effective traps, which claimed the lives of many soldiers, but nothing was as effective as the Vietnamese tunnel systems.

What were the Vietnam tunnels?

The biggest threat to the Communist Vietnamese forces was the American bombers that were capable of reaching the entire country and wiping out large areas in a single run. To counter this, the Vietcong dug hundreds of kilometers of tunnels around the country, which were designed in such a way that they could defend against anything.

Common tunnel defenses

The Entrance
One thing that quickly became apparent was the size differences in the country’s soldiers. Today, American men are an average of 6 inches taller than Vietnamese men, and during a time when there were extreme food shortages in the country, this led to a very noticeable size difference between the soldiers of the two nations. The Vietcong turned this into an advantage by making the entrances to their tunnels very small.

The opening would often only be big enough for a Vietcong soldier without a backpack to squeeze through. Because they were dug like this, the Americans had the option of sending in their smallest soldiers to risk it or digging out the entire entrance until a larger tunnel could be reached, something that gave the Vietcong plenty of time to set traps and ambushes.

Water channels
These were used as defenses, hidden entrances, and protection against gas. As a defense, it was almost impossible for the Americans to get through a guarded water channel, and throwing a grenade around a flooded and curved tunnel wasn’t an option. They were often built close to the entrances to ensure that any gas or flame attacks from the enemy wouldn’t be able to make it through to the inside tunnels. Hundreds of hidden entrances were built just below the water line along rivers to allow troops to jump into the water and just disappear.

Nailed snakes
The jungles of Vietnam aren’t short of poisonous snakes, and a favorite tactic of the Vietcong was to nail them to a piece of wood just above a doorway. The snake would rest on the top of the doorway to avoid its body weight hanging off the nail, but would be very angry and immediately, but silently strike at anything that came into range.

Explosive traps
The classic trip wire or mine dug into the ground was very hard to detect in the cramped and dark conditions of the tunnels, and took the lives of many American soldiers. There was nothing special about the explosive traps they placed, but it was in an environment that made them especially effective.

Disabling traps
Secret trapdoors on the floor that were just big enough for a single foot were a favorite of the Vietcong. The traps would be designed so a person’s foot would become stuck to the point they would have to be dug out, which apart from taking a long time and leaving themselves open to attack, also had a huge psychological effect on the American troops sent down the tunnels.

(An illustration of the different sections within the tunnels)

How did the Americans deal with the tunnels?

There was no way of dealing with the threat of the tunnels from the surface because they were far too deep to destroy with artillery and too big to dig out. The only way was to send people down there to try and chase out, or clear any Vietcong they found, but this was obviously a very dangerous job and requires a special type of person.

A unit was set up called the “Tunnel Rats” and was made up of men who were no taller than 5 ft 5 in. Their goal was to clear out sections of the tunnel systems so the Vietcong wouldn’t be able to set a trap of appearing behind enemy lines, but this sounds much easier than it was.

Problems began right away with the things the troops were issued, such as the M1911 .45 cal handgun. This was the standard gun given to the tunnel rats as any kind of rifle was too big, but its large muzzle flash and extremely loud bang in such a confined space would often leave troops temporarily blinded. Troops would often choose handguns with a smaller caliber and preferably a silencer, but this still didn’t solve the problem of being stunned for a second or two after each shot.

The next major problem was gas, and a known trick of the Vietcong would be to let American soldiers into sections of the tunnels so they could fill them with gas. The Americans were well aware of this trick but still chose to go underground without wearing gasmasks, as they made it almost impossible to see and move properly, and would quickly get steamed up in the humid conditions.

Apart from all of the traps and risks of the tunnels collapsing, the single biggest threat came from the Vietcong who would defend their positions with a fanatical might and little regard for their own safety.

(One of the rooms within the tunnel system that would have been lit by a single candle or oil-burning lamp)

How many tunnel rats survived?

There were never more than 120 tunnel rats in the country at any given time, mostly due to them being a very specialized unit only used in specific conditions. Over the 7 years that the Tunnel Rats unit existed, there were around 700 personnel that fought in the tunnels, with a total of 36 confirmed deaths and about 200 wounded. This would put the injury rate at about a third of the total number of people in the unit, which is high in comparison to any other unit that fought in the war.

After the end of the war, many of the surviving tunnel rats experienced various illnesses and conditions from the chemicals they encountered in the tunnels, but nothing was as damaging as Agent Orange. This was a herbicide that the US dropped all over the country to kill trees and food crops, but the chemicals soaked into the groundwater and often ended up in the underground systems the tunnel rats had to crawl through.