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Gaza, Hamas and the risk to civilian life during Operation Guardian of the Walls: a brief analysis

This analysis by AOAV would not be possible without reporting from Sebastien Roblin who provided a comprehensive picture of the weaponry used in the conflict May 2021 here and here.

The human cost of the conflict

The latest figures claim that at least 253 Palestinians have been killed, 129 of whom were civilians.  Israeli figures state that 12 people were killed by rockets or other fire, or when running for shelter.

Some of the dead on the Palestinian side were killed as a result of the rockets fired at Israel falling short. The UN estimated that, of 242 Palestinians killed as of May 10th, 12 were killed by friendly fire.

The combined numbers of injured from both sides is in the thousands.

The Iron Dome

The Iron Dome is one of a number of advanced missile defence systems in place to protect Israel from threats. The system utilises radar to detect rocket launches, manages the threat level of the individual rockets, and intercepts the rockets that may land in populated areas. Rockets fired from Gaza that are going to fall in uninhabited areas are not intercepted.

Image source: Rafael Systems

What happens when Hamas or PIJ fires a rocket into Israel

The most important thing to note regarding the Iron Dome is that it is not 100% effective at intercepting rockets fired into its protective field. According to their own literature from RAFAEL (a company founded as the military research wing of the IDF), the Iron Dome has over a 90% success rate.

The system estimates a rocket’s trajectory and decides whether it will impact a populated area or not. According to the prevailing wisdom, “[…]the volume of missiles threatening the Israeli home front will always be greater than the number of interceptors, the system should function by classifying threat levels, defence priorities and red lines.”

The system in place is very good at stopping the rockets but, as we have seen above, rockets do get through and some Israelis have died from the thousands of rockets launched. This risk points leaders to the conclusion they must undertake ‘mowing the lawn’ i.e. culling the latest cohort of militants in Gaza to protect the homeland.

Rockets fired from Gaza

According to Israeli sources, Sderot, which is one kilometre from the Gaza border, had 5,000 rockets fall in its 2km2 borders between 2001–2010. 90% of Sderot’s residents report a rocket landing on their street or the one adjacent to theirs. Ten people were killed by Qassam rockets in Sderot between 2001–2010. Less than 500 people were injured.

In ‘Mass Casualty Potential of Qassam Rockets’ by Zucker and Kaplan, they estimate that, absent of the extreme lengths the population of Sderot take to protect themselves from Qassam rockets and the advanced defence systems in place, there would have been between 27 and 92 deaths over a ten-year period. This estimate is based on the average pay load of a Qassam rocket, which can be used to calculate a lethal blast radius, as well as incidents in which rockets have landed close enough to kill people.

The single highest casualty count from a Qassam rocket came in 2007 when an IDF training camp was hit near the Gaza border. Army recruits were sleeping in tents which provided little protection from the blast. There were five casualties who required life-saving interventions. In total, 76 soldiers were injured, with 11 severe and moderate casualties.

The casualties in the training camp came from a single rocket carrying a payload of between 5-15kg. The larger, Iranian rockets now being deployed by Hamas have payloads of between 100-200kg.These bring far greater range and destructive potential. A large rocket like the Fajr-5 has a range of around 75km and a large 90kg payload.10 These rockets can easily reach Tel Aviv and cause a large number of deaths (See image below from a 2017 RAND study).

Open-source researchers such as Fabian Hinz now surmise that Hamas and the PIJ have achieved even greater range from the rockets which they produce within Gaza’s borders (see below). The new breed of rockets fired from Gaza are built using technical expertise from Iran.

It is important to note that some of the casualties in Gaza came from at least 450 rockets falling short and landing in Gaza; the result was Hamas killing its own civilians and destroying infrastructure.

Israeli air strikes

The IAF (Israeli Air Force) has destroyed tunnels, rocket firing sites and buildings used by Hamas. These actions are often caught on video. They use 2000lb GBU-3,1 (V)4/B bunker-buster bombs to destroy entire buildings.  The IDF claim that when they destroy these buildings, they are targeting key military installations or figures. Their critics say that they unnecessarily kill civilians.

To their supporters, the IAF fulfill the legal requirements for military action to prevent loss of civilian life. The steps they say they take to protect human life involve calling residents in a building that is targeted, saying in Arabic: “How are you? Is everything okay? This is the Israeli military. We need to bomb your home and we are making every effort to minimize casualties. Please make sure that no one is nearby since in five minutes we will attack.”

Critics claim that five minutes is often insufficient to clear the buildings of all residents, and does not also account for the reverberating harm such air-delivered weapons might bring.

The practice of roof knocking was adopted to further prevent civilian deaths. If residents did not respond to phone calls and could not be seen to exit the targeted building on reconnaissance drone footage, the IDF developed the practice of firing low-yield munitions at the roof the building. This tactic was first used at scale in OP Cast Lead.

It is surmised that the IDF use ‘Sledgehammer’ missiles for roof knocking. These are low-payload, high accuracy missiles with proximity detonation capability. This means they can detonate above the roof top, further limiting danger to civilians. Once it is confirmed that residents have vacated a building, the IAF claims that this then clears the fighter for attack and the target is destroyed. The IAF claims that they select the appropriate munitions for a strike to ensure that they achieve the desired effect with minimal damage to untargeted structures and people. This means that they can use bombs with payloads as small as 285lbs for precision strikes. Such claims, however, often do not mitigate civilian harm. Many of these claims are as contested as they are defended.

What happens when the IDF destroys a target in Gaza (aftermath and consequences)

The IDF claim they have carried out 1500 strikes in recent weeks.

The aftermath of the strikes carried out by the IDF in Gaza has been extensive. They destroyed:

  • Over 1000 buildings
  • 58 educational facilities
  • 17 medical facilities
  • Gaza’s largest bookstore
  • Electricity cables, sewage pipes
  • Half of the water pipeline network

The IDF have also been reported to have damaged 17,000 buildings.

Given the numbers of dead, the majority of strikes by the IDF did not kill civilians, but they very likely injured someone every time. Such deaths and injuries counter some of the claims of due diligence in the declaration and the application of force. Certain strikes, specifically those on tunnels built by Hamas under residential buildings, wiped out entire families.

Weapon precision and target legitimacy

Below you can see an image released by the IDF illustrating the proximity of civilian infrastructure to legitimate military targets.

The published data on the bombs that the IAF use to destroy high-rise buildings in Gaza includes the ‘circular area probable’, which gives the circle within which there is a 50% chance of the weapon landing. The JDAM system used by the IAF increases the placement accuracy of their bombs significantly with GPS guidance. JDAM bombs have a CEP of 13m, meaning they can be sure of hitting a target within a 13m diameter circle 50% of the time. More advanced ‘smart bombs’ can achieve higher accuracy with manned guidance and deployable wings. But such ‘smart bombs’ are still massively destructive.

So, while this level of accuracy is desirable, it still means that the kindergarten pictured above has a significant risk of being destroyed – even by fragments and shockwave from the blast.

Many deaths in Gaza occurred when tunnels, destroyed by the IDF, collapsed under civilians which destroyed their homes and, sometimes, wiped out entire families.

The Geneva International Centre for Humanitarian Demining (GICHD) points out in its comprehensive report on explosive weapons that: “accurately and precisely striking a target with a large munition such as a 227 kg (500 lb.) class bomb does not obviate its significant area effects and potential impact on civilians and civilian objects.”

They go on to point out that: “The effects of high explosive munitions within populated areas are influenced substantially by the presence of built structures and geographical features. Structures may provide protection from primary and secondary explosive weapon effects, but also amplify these effects due to the channelling and reflection of blast waves […]”

“The intuitive reflex among humans to seek shelter from an explosive weapon attack in buildings, vehicles and similar enclosed spaces poses a lethal risk. The intensification of the weapon effects in a populated area is mainly due to the reflecting blast waves and presence of a number of people and structures within the amplified effective range of a munition(s), as well as sources of secondary fragmentation. This results in a higher proportion of fatalities than would be likely in open spaces.”

To sum up: It is not simply pieces of shrapnel or a fireball that kill people in urban areas when a bomb is dropped. Pieces of building and, most importantly, the blast pressure can crush limbs, destroy internal organs, and kill people in places they thought were safe from the initial explosion.

No amount of Israeli claims that they are very careful to protect civilian lives reduces the point that, when an explosive weapon is used in a populated area, it will kill or injure civilians more often than not.

Borj Al Jalaa

If we take the destruction of Borj AL Jalaa (the HQ of the Associated Press and Al Jazeera) as an example, we can see what kind of risk to civilians the destruction of a tower using medium-high payload bombs would pose.

The USA releases data on the risks to friendly forces from ordnance. Looking at the data for the 500lb, Mk-82 bomb, we can see there is a 10% chance that an individual lying prone on the ground 250m away would be incapacitated i.e. a soldier would not be able to function in battle five minutes after the bomb exploded. This estimate is based on the fragmentation pattern of the bomb and doesn’t include other factors such as the fragmentation of buildings.

We can visualise the effect of a 500lb Mk-82 bomb using satellite imagery of Gaza from Solar Earth:

Notice that there is a good chance that high velocity debris would have reached both mosques in the bottom of the image. There is also a chance that shards could have reached the running track approximately 270m away. These could have caused significant injury. 

The blast pressure from one Mk-82  would have been sufficient to kill anyone in the neighbouring tower or give them severe internal injuries.

DF precision

The IDF are careful to select the appropriate size of weapon for the task. Video footage shows the ordnance impacting from an angle near the base of the building. It appears that the IAF may have used much smaller bombs to destroy Borj Al Jala. From examination of this video, it seems that seven bombs in total were used to destroy the building. The shockwaves didn’t appear to damage neighbouring buildings to a significant degree. This suggests that, either the majority of the blast occurred underground (implying that ’bunker buster’ bombs were used), or the bombs were of much smaller payload. They may have been the GBU-39 – a Small Diameter Bomb (SDB) designed to fit inside an F-35. These are highly accurate munitions that can be dropped at a great height to penetrate up to a metre of reinforced concrete below a metre of earth. Much larger conventional bombs (2000lbs) are required to achieve the same level of destruction against similarly fortified targets.


It is clear that the IDF take greater care to protect civilians than do militant groups in Gaza. It is, however, also clear that the death toll and human suffering is far greater in Gaza than it is in Israel. So, while Hamas are careless, the IDF could be described as callous.

The IDF are on solid legal ground when attacking military infrastructure, the problem being the infrastructure is interwoven with ordinary peoples’ lives. The IDF should acknowledge that they will inevitably kill civilians, who can’t escape the conflict when destroying military targets in Gaza, and possibly find other ways to destroy military targets.

Gaza’s factions, in turn, should stop committing the war crime of firing rockets from residential areas towards other residential areas which would, in turn, not provoke a violent response from Israel.

Both uses of explosive weapons against populated areas is wrong, and no amount of philosophical or political debate detracts from this one point: that when explosive weapons are used in towns and cities, 90% of those killed or injured will be civilians.