[News in War History] Hamas's Hidden Fortress, the 'Gaza Metro' Tunnels... Why It Calls for a Prolonged War

Tunnel Networks Longer Than Seoul Subway
Used Diversely on Both Land and Water Since Ancient Times
US Forces Struggled in Vietnam and Afghanistan Wars

The Israeli military is reported to have engaged in its first combat with the Palestinian armed group Hamas inside tunnels in the Gaza Strip, raising concerns about a prolonged war. These tunnels, referred to as the 'Gaza Metro' due to their length and complexity, have sparked fears that the Israeli military's operation could extend indefinitely.

Hamas has connected tunnels spanning over 400 km throughout the Gaza Strip, reportedly installing various traps and storing a significant amount of military supplies inside. Analysts both inside and outside the Israeli military warn that even if the complex urban warfare is concluded, unless all these tunnels are fully captured, Hamas could revive, predicting a very long conflict.

The appearance of Hamas tunnels discovered in the Gaza Strip and border areas, revealed by the Israel Defense Forces (IDF) in 2014. It is known that tunnels extend over 400 km throughout the Gaza Strip. [Image source=AP·Yonhap News]

These tunnels have been actively used for both defense and offense since ancient times. There is even a military term called 'Tunnel Warfare.' In this article, we will explore the scale and power of Hamas's extensive tunnel network, as well as the long history of tunnel warfare in human military history.

◆News: Israeli Military Engages in First Combat Inside 'Gaza Metro' Tunnels... Concerns Over Prolonged War

[Image source=EPA Yonhap News]

Let's first look at the news. According to the Times of Israel on the 2nd (local time), the Israeli Army Engineering Corps announced that it had launched a large-scale operation to destroy Hamas tunnels.

The Israeli military engineering corps stated that they are advancing by destroying traps set by Hamas and taking control of Hamas's underground fortresses using various types of robots and explosives. It is known that the Israeli military has so far targeted about 100 tunnels. As the Israeli military entered Gaza City, the central city of the Gaza Strip, and engaged in urban warfare, combat began with Hamas forces hiding in underground tunnels, increasing concerns about a prolonged war.

In particular, the tunnels dug by Hamas in the Gaza Strip are reportedly over 30 meters deep and have a total length of 483 km, making them larger and more complex than the Seoul subway system. Hamas has been building this tunnel network since 2005, and Western countries, including the United States, have nicknamed it the 'Gaza Metro.'

Concerns have been raised both inside and outside the Israeli military that capturing the Gaza Metro will not be easy. Yair Golan, former Deputy Chief of Staff of the Israeli military, pointed out in an interview with the Israeli Army Radio, "Entering tunnels where Hamas is hiding and waiting is a grave mistake," and suggested, "It is wiser to find and block the entrances or inject smoke to force the enemy out."

Given the already difficult urban warfare in the densely populated Gaza City, the Israeli military faces significant challenges as it must advance by systematically destroying these tunnels one by one.

◆History 1: Tunnels Mainly Used in Sieges... The Long History of 'Tunnel Warfare'

The image shows the 'Gungsan Tunnel,' a military tunnel installed during the Japanese colonial period, located in Gayang-dong, Gangseo-gu, Seoul. [Image source=Seoul City]

The tunnels used by Hamas as fortresses have been widely utilized for both attack and defense since ancient times. Tunnels were frequently used in siege warfare, which mainly targeted stone or wooden fortresses. Such battles, where both attackers and defenders competitively dug tunnels to gain an advantage, were called tunnel warfare.

Attackers often dug tunnels around fortress walls to create shelters blocking arrows shot by soldiers stationed on the walls or dug tunnels directly beneath the walls to collapse them as an offensive strategy. Consequently, when the enemy began digging tunnels, the defenders inside the fortress would dig counter-tunnels to discover and destroy the enemy's tunnels.

According to 'Historiai,' compiled by the ancient Greek historian Polybius in the 2nd century BC, during the siege of Ambracia between Rome and the Greek Seleucid dynasty, the Roman army surrounding the fortress created tunnels to block attacks from enemies on the fortress walls. The Roman army, known for its well-equipped engineering corps, frequently used tunnels in both defensive and offensive strategies.

After the Middle Ages, with the development of gunpowder weapons, strategies involving digging tunnels under fortress walls and detonating explosives to collapse the walls became common. During the 1453 siege of Constantinople between the Ottoman Empire and the Byzantine Empire, both sides engaged in intense tunnel warfare, with records indicating that the Byzantines won the tunnel warfare by collapsing the Ottoman tunnels.

Examples of using tunnels to attack fortresses also appear in the Annals of the Joseon Dynasty. On May 29, 1812, during the suppression of the Hong Gyeong-rae Rebellion at Jeongju Fortress, government troops reportedly dug tunnels beneath the fortress, buried large amounts of gunpowder, and detonated it to collapse the fortress walls, then attacked inside to quell the rebellion.

From the 19th century, when artillery technology greatly advanced, defensive fortresses built with trenches and tunnels became more common. In the late Pacific War during the 1940s, when Japan's defeat was imminent, many tunnels were constructed across Korea by the Japanese. A representative example is the 'Gungsan Tunnel' in Gayang-dong, Gangseo-gu, Seoul. It is known that the Japanese forcibly mobilized residents to build this tunnel for the defense and ammunition storage of the nearby Gimpo Airfield. Today, it is used as a historical exhibition hall.

◆History 2: Vietnam's 'Cu-Chi Tunnels' That Troubled U.S. Forces and Afghanistan's 'Taliban Tunnels'

The Cu-Chi Tunnel, a tourist attraction in Ho Chi Minh City, Vietnam. [Image source: Vietnam National Administration of Tourism]

Defensive tunnels continue to be used in modern warfare. No matter how much bombing is carried out with state-of-the-art bombers, ballistic missiles, or unmanned aerial vehicles (drones), tunnels cannot be completely eliminated, making them fortresses for prolonged resistance, especially for weaker nations.

During the Vietnam War in the 1970s, which ended in a shocking defeat for the U.S., tunnels were known to be the most exhausting challenge for U.S. forces. The 'Cu-Chi tunnels,' now a tourist attraction in Ho Chi Minh City, Vietnam, show traces of the extensive tunnel fortresses used by North Vietnamese forces at the time.

Originally, these tunnels were built during Vietnam's independence war under French colonial rule starting in 1946. They spanned about 250 km across Vietnam and were very narrow, so tall U.S. soldiers could barely enter. Numerous traps were installed throughout, making it very difficult for U.S. forces to suppress them.

In the 2001 Afghanistan War, U.S. forces also faced great difficulties due to tunnels used by the Taliban and Al-Qaeda. The so-called 'Taliban tunnels' in the Tora Bora region of eastern Afghanistan, surrounded by mountain ranges over 4,000 meters above sea level, extended up to 350 meters underground. These tunnels neutralized not only U.S. bombers but also bunker-buster weapons designed to destroy underground structures, gaining notorious fame.

◆Implication: 'North Korean' Technology Presumed to Have Been Used in Constructing the Gaza Metro

The appearance of the Third Tunnel, a North Korean invasion tunnel discovered in 1978 in Jangdan-myeon, Paju-si, Gyeonggi-do. [Image source: Paju City official website]

Tunnels used in various wars are also closely related to South Korea. Since the 1970s, North Korea's infiltration tunnels have been discovered along the Korean Demilitarized Zone. Officially confirmed North Korean infiltration tunnels number four, from the 1st to the 4th tunnels, with several more presumed to exist.

Some have suggested that North Korea's tunnel digging technology may have been diverted to the construction of Hamas's Gaza Metro. On the 17th of last month, Sarit Zehavi, head of the Alma Research and Education Center, an Israeli security organization, stated in an interview with Radio Free Asia (RFA), "It is unclear whether Hamas directly obtained tunnel technology from North Korea," but added, "North Korea passed the technology to Hezbollah, and it seems that the technology transferred to Hezbollah ended up in Hamas's hands."

As a result, the progress of the Israeli military's prolonged clearance operation in Hamas tunnels will likely remain a keen focus not only for Israel but also for the governments of South Korea and the United States.