The Subterranean Front: Lessons for Defeating Underground Threats From a Commander on the Front Lines
Israel’s 2023-2024 full-scale war against Hamas in Gaza marked a watershed moment in the history of warfare: the subterranean domain became, for the first time, the primary theater of combat, command-and-control, logistics, resupply, and maneuver in a major war.
Through almost three years of near-continuous action against enemies in the subterranean domain, the Israel Defense Forces (IDF) have gleaned hard-won lessons for how to conduct operations in this unique and challenging environment. This report, co-authored by the person tasked with finding and neutralizing tunnels for the Israeli military—the former Commander of the Yahalom unit, the IDF’s elite combat engineering unit—distills those lessons and details how Israeli, U.S., and partner militaries can implement these lessons and prepare to face adversaries lurking belowground.
Tunnels have been utilized in wartime for thousands of years, dating back to the Peloponnesian War, and featured prominently in World Wars I and II, the Vietnam War, and the Global War on Terrorism, among other wars. But now, adversaries possess the tools and know-how to build tunnels with remarkable ease and sophistication.
Both Hamas and Hezbollah sought to use subterranean warfare to neutralize Israel’s technological superiority and reduce the IDF’s conventional advantages. For over a decade, Hamas transformed its Gaza tunnel network into a complex, multi-layered subterranean system, including command, logistics, movement, and survival arrangements. To Israel’s north, Hezbollah similarly adopted a subterranean system with order-of-battle logic to counter any Israeli ground invasion—and stage its own.
Difficult battlespaces are nothing new for Israel. Yet the complexity of the subterranean domain still posed a massive challenge to this first-class, adaptive military.
Like Israel, the United States faces subterranean threats along its borders. In June 2026, officials uncovered a sophisticated tunnel between the United States and Mexico, reportedly a storage and transit hub for firearms and explosives. This was not anomalous. Since 1990, American security officials have located at least 236 cross-border tunnels entering the United States—potentially just a fraction of the total that exist.
Nor are underground threats only a problem for America’s homeland security—they pose a risk to U.S. interests worldwide. The U.S. military will almost certainly have to detect, neutralize, and potentially fight in the subterranean domain abroad in the future.
Now, Israel has extensive, hard-won operational experience confronting subterranean threats that can help inform and prepare U.S. forces to fight against adversaries who seek to gain advantage from burrowing underground. Israeli elite combat engineering forces, led by one of the co-authors, have spent nearly three years locating, mapping, and neutralizing terror tunnels.
These forces have been operating in Gazan and Lebanese tunnels where every step forward is fraught with danger; where an almost superhuman level of concentration and bravery is required; and where troops conduct painstaking work without sunlight, fresh air, or even a moment’s rest. Those subterranean efforts are unearthed for the first time in this paper.