Perspective: Potential Consequences of Israel's Ground Offensive in Gaza

According to two leading experts on urban warfare, a ground attack by Israel on Hamas' base in the streets and tunnels of Gaza is expected to be lengthy, violent, and intricate.

Colonel (Ret.) Liam Collins and US Maj. (Ret.) John Spencer collaborated on the book titled "Understanding Urban Warfare." Collins, currently the executive director of the Madison Policy Forum, is a senior fellow with New America and also an officer of the US Army Special Forces. Having served for 27 years, Collins has extensive experience with numerous deployments to Afghanistan and Iraq.

Spencer, the chair of urban warfare studies at the Modern War Institute at the US Military Academy at West Point, has extensive military experience, including two combat tours in Iraq. In their assessment, they expressed concern over Israel's readiness for the anticipated large-scale urban combat in Gaza. This particular operation could extend over several months due to the challenges faced by even a sophisticated military like the Israel Defense Forces (IDF) when fighting in an urban environment.

The experts noted that although Israel has certain advantages, such as specially designed armored bulldozers for urban combat and proficiency in nighttime operations, these must be balanced against their limited experience and training in urban warfare. Meanwhile, Hamas has over 200 hostages, utilizes human shields, employs suicide bombers, constructed tunnels, set booby traps, and holds numerous civilians captive, having fortified its position for years.

If the Israeli invasion proceeds, the experts estimate that the IDF will devastate "80 to 90" percent of Gaza's urban zones, fundamentally altering the region's landscape for decades to come.

PETER BERGEN: What is the IDFs record on urban warfare of this type?

JOHN SPENCER:  Not much.

The IDF's greatest shortfall lies not in their training areas or tanks, but rather in their lack of expertise in executing swift and efficient large-scale urban operations. It should be noted that this deficiency is not unique to the IDF, as even the United States military is not adequately trained, staffed, or equipped for such urban battles. During a visit to Israel, it becomes evident that their urban training center, like those of other militaries, falls short of the necessary standards required for combat in places like Gaza.

Israel has displayed considerable prowess in conducting successful antiterrorism operations in Jerusalem and other parts of the country. However, this expertise does not necessarily extend to conducting large-scale military operations in urban settings.

SPENCER: A multitude of uncertainties lie ahead, encompassing Hamas' capabilities, ranging from surface-to-air missiles to the unknown preparations they may have made in anticipation of a potential Israeli retaliation.

BERGEN: Now, let's dive into the challenges that Israelis encounter in Gaza, which include the presence of hostages, human shields, suicide bombers, tunnels, cross-border tunnels, improvised explosive devices, booby traps, and a large number of civilians. Additionally, there is no element of surprise in this situation.

Due to international pressures, there may be political motivations for the Israelis to keep this operation in Gaza as brief as they can. However, from a military standpoint, it is possible that this operation could extend over several months.

SPENCER:  I say it would take months to do the mission in Gaza.

Israel continues to deploy soldiers and armored vehicles along the Gaza border in Zikim kibbutz of Ashkelon, Israel on October 14.

Mostafa Alkharouf/Anadolu/Getty Images

In a densely populated urban area, an advanced military like the IDF faces disadvantages and limitations. They are unable to utilize advanced technologies to launch pre-emptive strikes against the enemy before engaging in close combat. This makes urban warfare exceptionally challenging as the superior advantages possessed by a large military are diminished, and in certain circumstances, even nullified.

The ability to execute "combined arms maneuver" is lost when operating in urban areas. This military strategy, which has been employed since World War II, relies on mobile forces that can navigate the enemy's positions and surround them. However, urban environments do not allow for such maneuverability. No military desires to confine its forces to a single street or multiple streets.

To illustrate this on a tactical level, there are numerous instances where the enemy can conceal themselves and move undetected by intelligence surveillance and reconnaissance platforms or drones flying overhead. The use of tunnels allows them to evade detection while moving. Moreover, they can transition between buildings by demolishing walls, further complicating the situation. Additionally, even if the enemy is spotted, it is not always feasible to engage them due to obstacles such as other buildings obstructing the line of fire. Throughout all these challenges, it is vital to consider the presence of civilians in the area and ensure their safety.

There are so many opportunities for the enemy to hide and move without being observed by the intelligence surveillance and reconnaissance platforms, or drones up in the sky.

Liam Collins

SPENCER: They lose the effectiveness of their weapons in urban warfare where most standard-issue weapons may not penetrate enemy-occupied buildings. There are some weapons that can, but they are not the majority.

BERGEN: Why?

I will provide an example. In 2002, we launched two 500-pound bombs on a small compound located in a rural area of Afghanistan. Surprisingly, a Taliban fighter managed to survive the bombing and retaliated by throwing a grenade at us. These structures naturally offer defense advantages to the defender. When witnessing the destruction of a building, one would assume that no one could have survived such an impact, but it is not uncommon for people to survive.

Hamas aims to prolong the urban conflict as much as possible. The longer the fighting persists within cities, the more political pressure will mount on Israel to halt the attack due to the consequential harm inflicted on civilians and the inevitable collateral damage. Their objective is not to annihilate the IDF, as this is unattainable. Instead, their aim is to gain additional time.

BERGEN: Do the Israelis have any advantages?

SPENCER: Yes, they have D9 Bulldozers. These are two-story remote-controlled bulldozers that can move forward and neutralize the enemy's advantage. Hamas benefits from hiding in concrete buildings. However, if you lead with an armored bulldozer that can withstand attacks like RPGs (Rocket Propelled Grenades), you can eliminate the enemy's protection provided by concrete buildings. This is one of the low-tech solutions developed by the IDF, which the US military currently lacks.

COLLINS: The Israelis possess effective night-fighting capabilities, which gives them an advantage when conducting attacks during nighttime as it aligns more favorably with their strengths compared to the enemy.

BERGEN: In the absence of overhead imagery, how do you determine the appearance of the tunnels?

SPENCER:  The overhead imagery wont help you at the depth that some of these tunnels are at. You have to have specific underground mapping technologies.

Israeli soldiers patrol near the Gaza border as the clash between Israeli army and Palestinian factions continues in Nir Oz, Israel on October 24.

Mostafa Alkharouf/Anadolu/Getty Images

BERGEN: How about utilizing robots and tear gas in tunnels?

SPENCER: Tear gas presents an efficient measure for evacuating enemy personnel from a structure, while preserving its physical integrity. Due to the potential political implications, it is doubtful that Israel would employ this method. After all, what message would be conveyed if Israel were to resort to gas usage?

BERGEN: In your book, you mention David Kilcullen, an Australian strategist, who stated that "Cities are sponges for troops." Why did he say that?

SPENCER: This is because of the immense force required to clear even a single street. It is not possible to rely solely on bombing as a strategy. A smaller urban defender can effectively tie up a large military force. However, this does not mean that capturing cities is impossible. It simply necessitates a significant amount of force, power, and a substantial number of soldiers.

COLLINS: The urban environment presents another challenge as well. Simply clearing an area is not sufficient, as the enemy may return through tunnels or the walls of nearby buildings. They can easily catch us off guard and reclaim the area or a building as soon as we vacate it.

BERGEN: Dealing with snipers is a difficult task. It is safe to assume that Hamas has trained snipers who are deeply entrenched and possess excellent knowledge of the terrain.

SPENCER: Numerous valuable insights have been gained over the past two decades of urban warfare, with one example being the development of acoustic sensors capable of pinpointing the location of snipers.

Additionally, one notable technique utilized by IDF soldiers involves the use of oversized bags that extend to the top of their heads. This unique form of camouflage is strategically employed to deceive snipers, effectively concealing their helmets.

BERGEN:  What about robots on the Israeli side?

COLLINS:  They will, without a doubt, employ them, but they probably dont have as many as they would like, and theyre slow.

BERGEN: Hamas offers waste management services and some social welfare programs. It assumed office in 2006 through an election, with no subsequent elections conducted. However, the group operates in various capacities, including its involvement in terrorism. Does this create complications?

COLLINS: There is this dual nature of Hamas, functioning both as a terrorist and paramilitary organization while also delivering governmental services.

Israel, despite acknowledging the unrealistic aim of "destroying" Hamas, is focused on degrading the organization and preventing future attacks. Their primary target is the leadership, the terrorist wing, and the fighting wing of Hamas. The operation will conclude when they determine that the diminishing returns of further degrading capability outweigh the political costs of continuing the operation.

BERGEN: What does the aftermath of conflict in Gaza entail?

COLLINS: It involves the return of people to their homes, clearing debris, and efforts to restore basic services. Non-governmental organizations are also stepping in to help reinstate a sense of normalcy for the Palestinian population.

Israel's Defence Minister Yoav Gallant meets soldiers in a field near Israel's border with the Gaza Strip, in southern Israel October 19.

The Israelis withdrew from Gaza in 2005 due to the significant difficulties it posed. When I spoke to Israelis about this, they clearly stated that they have no intention of maintaining control over Gaza. Therefore, the question arises as to who will assume responsibility for Gaza.

SPENCER: The track record of militaries in terms of state-building, nation-building, or city construction is extremely poor. The question of who will govern Gaza and take charge of providing essential services, security, and reconstruction is of immense significance.

BERGEN: Turning our attention to Mosul, the second largest city in Iraq, which was captured by ISIS in 2014. In your book, you discuss the staggering amount of one hundred billion dollars in damages inflicted upon the city during the operation to dislodge ISIS from late 2016 to 2017.

SPENCER claims that ISIS spent two years preparing and fortifying their defenses in Mosul, resulting in a nine-month battle led by security Iraqi forces. These forces, although not as formidable as the IDF, received support from the US and utilized the most advanced air power to systematically destroy a significant portion of Mosul's buildings.

This outcome serves as a clear indication of what can be expected if the IDF undertakes a similar mission. The destruction caused in Gaza's urban areas is estimated to impact approximately 80 to 90% of the infrastructure and buildings, significantly transforming the landscape for future generations.

COLLINS: It is important for individuals to understand that the destruction of cities is sometimes necessary to achieve objectives, even in situations where strict war laws apply.

BERGEN: Can you explain how tanks fare in urban environments and discuss the advantages and disadvantages they bring to the table for Israel, considering their tank-focused military strategy?

In the open desert, tanks enjoy a significant advantage. However, their strengths are greatly diminished when operating in urban environments. Their ability to engage targets from a distance is severely limited, and they are unable to elevate their main gun to target enemies in tall buildings. Therefore, while tanks are still essential in urban combat as part of a combined arms team, they are much more vulnerable in this setting compared to other environments.

Liam Collins

SPENCER:  Of all the challenges inherent to this type of urban combat, the tank is extremely vulnerable.

The tank is an indispensable tool in urban warfare, as it can withstand the defense and maneuver through streets with ease. Its ground forces possess unparalleled firepower, capable of breaking through concrete walls. However, it does have limitations in terms of visibility and vulnerability. Its slow speed makes it easily detectable, thus requiring infantry support for protection.

BERGEN: Therefore, there is a need for a significant number of infantry to provide protection for the tank?

SPENCER: Exactly. The Ukraine war taught us this lesson; Russia relies heavily on artillery and tanks, and when they crossed into Ukraine in early 2022, their limited infantry support resulted in a staggering loss of tanks.

COLLINS: The infantry is necessary to protect the tank, and vice versa, as they provide mutual protection.

BERGEN: Are there implications regarding the "mass" aspect when initiating a military operation in Gaza? Is it easier to defend than to attack?

SPENCER: The term commonly used is "combat power." In open terrain, the ratio of combat power required is usually three to one, or sometimes simply referred to as troops, in comparison to the defender. However, in urban terrain, it has been historically observed that combat power needed is around fifteen to ten times greater due to the inability to concentrate forces in urban areas.

The presence of a single street may necessitate the deployment of an entire battalion in an attempt to navigate through it.

BERGEN:  And a battalion would be 800 troops?

SPENCER:  Up to 900.

BERGEN: Let's consider the magnitude of the force required to be sent into Gaza in terms of numbers.

SPENCER: There are many factors to consider, but the focus should be on strength, not quantity. This is not akin to the Battle of Berlin in 1945, where the Soviets deployed a battalion on every street. Urban battles nowadays tend to occur repeatedly because no country possesses a million-man army anymore. Instead, they have smaller armies, enabling a small opposition force to gain power within the urban environment. To remove them, a significant amount of combat power is usually necessary, often in the form of artillery.

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BERGEN:  Let me ask you, Liam, about the hostages because you come from the US special operations community.

COLLINS: I believe it is unlikely that they possess knowledge of the hostages' whereabouts. It is probable that the hostages are being hidden underground. Obtaining such intelligence is crucial for carrying out a successful operation. However, even with the necessary intelligence, ensuring a safe arrival and extraction, while maintaining a reasonable chance of success and preventing harm to the hostages and a significant loss of forces, poses a challenge.

Therefore, I believe nations are likely positioning their forces strategically, so that if they do acquire the necessary intelligence, they can assess whether a rescue operation should be attempted. However, I believe diplomatic efforts will be the most effective approach, as demonstrated by the recent release of the American mother and her daughter by Hamas.

Now, let's discuss the Israeli hostages. In my opinion, Hamas is likely to keep them for the longest duration.

SPENCER: The existence of numerous hostages from various countries, combined with the fact that they are situated among both the enemy and the Israelis who are about to carry out this operation, creates an unprecedented situation, in my opinion.

To have this many hostages from this many countries intermixed with the enemy and the Israelis about to execute this operation is an unprecedented situation.

John Spencer

BERGEN: What motivated you to author a book on urban warfare?

COLLINS: Given the rising prevalence of battles occurring in urban environments, it has become evident that military forces globally, including our own in the US, lack the necessary preparedness. Continually, I challenge individuals to identify a noteworthy conflict in Ukraine that does not take place within a city.

SPENCER: Militaries have a natural aversion to urban warfare, which is not their preferred terrain. Consequently, they tend to neglect proper preparation, allowing the enemy to persist with such tactics.

COLLINS: However, it is inevitable for militaries to engage in urban warfare since wars are fought by humans, who predominantly reside in urban areas.