In the Iron Swords War, the IDF was exposed to a different reality in Gaza from the one it once knew, or thought it knew, because IDF’s last maneuver in the field occurred a decade earlier, in Operation ‘Protective Edge’.
They knew that Gaza was networked with tunnels, but never imagined they would discover tunnels in such dimensions in terms of their scope, depth, system, and sophistication, including the connecting points between the various tunnels. They did not know that the underground network allowed Hamas terrorists to enter the tunnel in the Philadelphi corridor and end up above the ground in the northern part of the Gaza Strip. They did not realize that hostages could stay inside for a long period and did not know that they were connected to civilian infrastructures such as hospitals. The professional building of the tunnel network indicates that they used external help and expertise.
The IDF needed quite a long learning time to deal with the tunnels that were gradually unfolding, since entering the tunnels is complex to begin with – usually via hidden, narrow, and sometimes very deep shafts.
But over time they managed to deal with it, and could also tell the difference between tactical tunnels that were used for combat and attacks, and strategic tunnels that included equipped and advanced command and control rooms, which supported the tactical tunnels and were essential for Hamas activity.
The next challenge the IDF had to face was how to destroy the tunnels. After various strategies were examined, such as flooding, which was proved unsuccessful, other methods were developed, apart from the use of explosives. The IDF continues to this day to uncover the underground infrastructure, but it is complex due to the enormous number of tunnels and their ramified structure. Moreover, the tunnels must first be discovered.
The tunnel in Rafah where the bodies of the six hostages were found at the end of August, was unfolded almost by accident since its shaft was hidden inside a children’s room in a residential building. Imagine how many more shafts are out there, especially in densely populated or ruined areas.
However, the IDF has already learned about the close connection between the civilian infrastructure, the population, and the tunnels. Not only do they know that Gaza citizens participate in the digging, but they know also about the critical importance that Hamas attaches to the symbiosis between life above and below the ground: there may be a shaft in every school and a tunnel under every hospital. The connection between the upper construction and the lower construction adds to the complexity.
As a result, the IDF has developed a new theory for underground warfare. There is no other army in the world that faces such a threat at such a level. And apparently, this is not over yet. Until the IDF leaves the Gaza Strip – if they ever will – they will continue to learn, improve, and develop capabilities and new fighting methods. Other armies worldwide are already learning from the IDF.
The bad news is that Hamas tunnels are not an unusual phenomenon among our enemies. We discovered the giant tunnels penetrating from Lebanon already in 2018, and only recently, underground routes – albeit short ones – were located in Tulkarm and Jenin as well. This will have consequences on the IDF’s forces, which will require more engineering forces, expanding units such as the Yahalom (Special Operations Engineering Unit), and investing in the development of combat measures and methods.

Published in Ynet, October 24, 2024.