Hamas’s Tunnel Warfare Harks Back to the Viet Cong

Israel’s ground war in Gaza is now underway. As the Israel Defense Forces (IDF) approach Gaza City from the north and east, many U.S. military analysts are forecasting gruesome urban fighting and referencing the U.S. Army’s and Marine Corps’ brutal lessons from Iraq, including house-to-house fighting in Fallujah in November 2004 and the nine-month siege to liberate Mosul from the Islamic State in 2016 and 2017. While these analogies may offer insight into the grueling intricacies of urban warfare ahead, they fail to account for the additional complexities the Israelis are facing in Gaza. The IDF’s fight will be harder and longer than the Second Battle of Fallujah and more violent than the Mosul offensive.

Gaza’s sprawling maze of tunnels represents an aspect of war not faced by the U.S. military during the wars in Iraq and Afghanistan. Indeed, the underground fighting has begun: On Tuesday, Israel said its forces had entered Hamas’s vast tunnel network and attacked the militants there. To find a more appropriate parallel from U.S. combat history for this kind of warfare, we need to go back much further in history—to the Vietnam War.

Throughout the Vietnam War, the Viet Cong’s tunnel systems, particularly those in the Cu Chi district of Ho Chi Minh City (then Saigon), played a crucial role in the awful drama of that conflict. Situated on the rural outskirts of what was then the South Vietnamese capital, the 150-mile-long Cu Chi tunnels were a maze of constricted passageways and cleverly concealed booby traps, often in total darkness.

U.S. superiority in bomber aircraft, artillery, mortars, and other capabilities was rendered moot by the subterranean labyrinths, which allowed guerrilla troops to ambush bewildered U.S. and South Vietnamese troops above ground and then disappear. The tunnels, intricately built by hand during the Indochina War in the late 1940s, served as living quarters, supply storage, and operational bases. They presented a domain of the fighting environment unseen and importantly unavailable to the Americans and South Vietnamese, and they made the war above ground exponentially more challenging. By 1968, the Viet Cong’s tunnel systems were emblematic of the United States’ grim experience in Vietnam: Underground, the U.S. military’s significant technical advantages devolved to fighting in tight, unfamiliar spaces with knives and flashlights. These tunnel systems spawned a group of specially selected American, Australian, New Zealand, and South Vietnamese soldiers known as “tunnel rats,” who were trained to fight in the highly dangerous subterranean domain. Only a tiny sliver of U.S. troops in Vietnam—approximately 700—served in this capacity.

Gaza’s tunnels bear a strategic and tactical resemblance to those of Cu Chi. As in Vietnam, these underground structures were first developed long before Hamas gained control of the region in 2007and have diverse purposes. Their sophistication and myriad uses will vex the IDF. There are the Hamas-controlled tunnels for weapons smuggling out of the sight of Israeli drones. There are commercial lanes that generate revenue from goods smuggled across Gaza’s border with Egypt. There are command and control centers, ammunition caches, and living quarters. But the most concerning aspect for Israel is the combat tunnels. These were pivotal in operations such as the capture of Israeli soldier Gilad Shalit in 2006, when militants used a tunnel to enter Israel near the Kerem Shalom border crossing. The kidnapped Shalit disappeared into these tunnels and remained captive for more than five years—another testament to how these tunnels provide defense advantages and will frustrate Israeli attempts to kill Hamas fighters and retrieve hostages alive. (That said, the IDF announced Monday that it had managed to free an Israeli soldier during its incursion into northern Gaza, one of the approximately 240 hostages Hamas took during its Oct. 7 attack on Israel.)

The 2.2 million Palestinian inhabitants of Gaza, most of whom are civilians, have long endured hardships due to blockades, economic challenges, and frequent outbreaks of violence. Largely unemployed and impoverished, they, like all people, aspire for sovereignty and self-determination as well as a life free from conflict. The tunnel network, while militarily strategic for Hamas, is also emblematic of the lengths to which some Palestinians feel they must go to ensure their security and resistance.

Tunnels in Gaza date back to the late 1990s. During the early 2000s, they served as conduits for smuggling goods and weapons between Gaza and Egypt beneath a border that was less fortified than it is today. Hamas’s investment in these tunnels—funded largely by Iran—is testament to their value. One tunnel discovered a decade ago stretched a full mile and a half into Israel and required $10 million and 800 tons of concrete to construct. Following the 2014 Gaza conflict, when the IDF discovered many of these tunnels during Operation Protective Edge, Israel implemented measures to curb the diversion of building materials supplied by Israel for tunnel construction. Despite these measures, an underground economy thrived, with materials readily available for building more tunnels.

Whereas Vietnam’s tunnels stretched over vast distances, Gaza’s are condensed into a much smaller area, leading to higher tunnel density and elaborateness. Furthermore, much of the soil in coastal Gaza is softer than that of southeastern Vietnam. As many analysts identified, the fighting in Fallujah and Mosul was tight and constricting. Fighting in the Gaza tunnels will be suffocating. Hamas will have every advantage, not least because the total depth and breadth of the underground network remains unknown to the IDF. Some estimates suggest more than 300 miles of tunneling beneath Gaza. With tunnels deep and wide enough for motorbike transport and reaching as far as 115 feet below ground, Hamas’s sheer engineering prowess and ability to invest strategically over decades have become evident. The challenges go beyond the physical to the psychological. As with the Viet Cong’s tunnel fighters, an enemy capable of popping out of the ground and then quickly disappearing below the earth can gain a psychological advantage by introducing confusion and paranoia.

The tunnel network’s significance expands when one considers the civilian backdrop of Gaza. The presence of civilians—particularly women, children, and older people—as well as aid workers and news cameras makes any large-scale military operation fraught with moral, ethical, and political pitfalls. It’s unclear how many among the Palestinian population in Gaza are Hamas fighters. The fates of combatants and civilians are intertwined, making the cost of each combat decision by the Israelis dramatically higher. The struggle for the narrative will be as challenging as the fighting, with each engagement and each day of fighting scrupulously dissected by analysts, international figures, and human rights groups. As evidenced by the initial misreporting by major international news organizations about the Oct. 17 explosion at Al-Ahli Arab Hospital—based on statements by the Hamas-controlled heath authority that blamed Israel—it is now easy to deploy and modify facts, statistics, and images to confuse or mislead large audiences. Important analysis by the New York Times and BBC reveals the circumstances surrounding the explosion remain unclear, although the available evidence suggests a misfired rocket from Gaza as the cause.

As it enters a ground war in Gaza that will reverberate throughout the region, Israel must navigate an already complex conflict with consideration for the future. In the coming weeks, regional leaders in Cairo, Amman, Riyadh, Abu Dhabi, and Doha will strongly condemn Israel. As gruesome videos of civilian casualties emerge from Gaza, Arab populations will demand public judgment and retribution against Israel from their leaders. Therefore, Israel absolutely must maintain the strong support of its principal backers, the United States and the European Union.

The ground war in Gaza will last months, if not years. As it goes on, Israel’s commitment to international law, human rights, and peacebuilding will be crucial in shaping U.S. and European opinion. The IDF must lean on its sophisticated public relations machine, justifying each strike and each action on the international stage, responding to each misstep with honesty and transparency. The tunnels running beneath populated areas make both tasks—limiting civilian casualties and staying on top of the narrative—all the more challenging. It will require careful oversight of the fighting in the tunnels, placing even more of the IDF’s troops at risk to reduce the possibility of killing civilians in Gaza.

The ground war will be a slog. Aside from the tunnels, the IDF in Gaza will face combat’s bleakest conditions: houses booby-trapped to explode, military installations concealed under schools, and weapons stored in mosques. Hamas uses civilians as human shields and hospitals as command centers. To all this, add an entrenched, underground enemy holding hostages—another layer of complexity within a set of unimaginably vexing conditions.

Historical parallels such as the Vietnam War and the urban fighting in Fallujah and Mosul offer important insights but fail to fully capture what’s ahead. The IDF confronts both a powerful adversary burrowed into the earth and a test of Israel’s moral compass and place on the world stage. The tunnels of Gaza symbolize a new paradigm in warfare, where every strike below ground has implications above. In the forthcoming months, as the world watches closely, Israel will face dual battles: one against an entrenched enemy in the tunnels and another in the global information space.