Israel Confronts Hamas: For Military Planners, Gaza is Not Unusual

Swift response: smoke billows following an Israeli airstrike in Gaza on 12 October. Image: Rizek Abdeljawad / Alamy

The legal and ethical challenges of operating in densely populated areas are going to be a tragic constant of 21st century warfare, with no easy solutions.

The impending ground invasion of Gaza by the Israel Defense Forces (IDF) has raised a range of questions about how military operations should be conducted in densely populated areas. The political context of the Israel–Palestine conflict, and the human tragedy that has engulfed Israeli and Palestinian families, has made the military considerations secondary to a raging political debate. For the military, however, the questions at stake are not exceptional but routine, and will likely define many of the planning considerations for operations throughout this century. Precedents set in Gaza, therefore, may cast a long shadow.

Israel has declared war on Hamas. Legally, there are two questions that arise: the legality of the war, and the legality of how it is fought. As regards the former, Hamas’s incursion on to Israeli territory, the deliberate massacre of over 1,300 and the kidnapping of hundreds of Israeli civilians undoubtedly counts as an armed attack in response to which Israel has the right of self-defence. Given that Hamas has a stated objective of destroying the Israeli state, took the hostages on to the territory it controls, and is launching rockets and conducting command and control from that territory, it is also legal for Israel to operate against Hamas on the territory of Gaza in response. There is therefore no question as to the legality of the Israeli action, which aims to eliminate the capacity of Hamas to conduct further attacks.

The difficulties arise as to how such a mission is to be carried out, given that the area of operations comprises densely populated urban terrain with a large proportion of children and non-combatants and very weak critical infrastructure. Under the Laws of Armed Conflict and International Humanitarian Law, Israeli forces are obligated to discriminate military from civilian targets, to restrict their activities to those that are of military necessity, and to exercise proportionality. It is not illegal for civilians to be killed as a result of operations. It is illegal for operations to target civilians or for there to be a lack of proportionality in striking military targets relative to assessed collateral damage.

Discrimination is simplified by the fact that Hamas systematically uses civilian objects for military purposes. It has dug subterranean infrastructure beneath civilian buildings, including ammunition depots, and has boasted in its own media about using Gaza’s water reticulation infrastructure for manufacturing rockets. When militaries do this, they render such areas military objects that are targetable, which is why – for example – it was legal for coalition forces to strike a hospital in Mosul that had been repurposed for IED manufacture in 2016. The challenge for the attacking force therefore becomes a question of judging the military value of a target against the risk of collateral damage.

The legal case for striking urban targets is often heavily weighted to the detriment of civilians because of the asymmetry in certainty about targets. If a Hamas command post is communicating from a structure and this is intercepted, if an Israeli ground unit takes fire from a structure, or if rockets are launched into Israel from a site, then there is confirmation that enemy military activity is taking place there. The civilians hiding in the building, trying to sleep or keep out of the line of fire, are invisible, and therefore are not counted in the judgement as to proportionality. This is why the RAF has long maintained that it knows of only one civilian killed in its strikes in Iraq, even though the civilian death toll from the air campaign during the war against Islamic State numbered in the thousands.

The laws of war are effective when parties view them as viable instructions for how to fight. When they prohibit fighting altogether, they are likely to be ignored

The campaign to defeat the Islamic State – which involved the assault of several major cities, from Ramadi and Fallujah to Mosul, Tel Affar and Raqqa – was conducted slowly, with painstaking targeting and legal processes to try and mitigate civilian harm. Nevertheless, the cities were laid waste, and thousands of civilians died. The death toll was also high for the attacking force. Iraq’s Counterterrorism Service, one of the most experienced and capable military units in the world at the time, suffered 40% casualties during the assault on Mosul.

The challenge of how to take urban ground without destroying the city is insurmountable with the tools currently available. Moreover, because there is no prize for second place in war, and because sensor dominance quickly leads to an asymmetry in casualties, weaker forces will retreat into dense, urban terrain. Ukrainian troops did this in Mariupol. British forces expect to have to operate from urban strongholds in future conflict. Hamas and Islamic State’s decision to fall back into urban terrain made sound tactical sense.

The laws of war are effective when parties view them as viable instructions for how to fight. When they prohibit fighting altogether, they are likely to be ignored. How to craft rules that protect civilians in this context, therefore, requires thoughtful proposals. The proposal advocated by some groups to exclude explosive weapons from urban fighting is a non-starter, as it would confer such an advantage on to the defender as to prevent an attacker from prosecuting operations.

For Israel, tactical options are constrained by a range of additional factors. Iron Dome – the air defence system protecting Israeli cities from rocket attack – has a finite number of interceptors. Given the massive threat if Hizbullah joins the fray, Israel is keen to limit its expenditure of interceptors by interdicting left of launch. The threat of escalation with Hizbullah also means that Israel feels it necessary to preserve combat power. Both factors lead to an approach to Gaza that is fast and favours firepower. This weights the judgement as to military necessity.

In the absence of tools and methods for fighting among the people, advertising intent and clear avenues for civilians to vacate the battlespace is a viable alternative. This is what Israel has done by instructing civilians to move South of the Gaza River, while indicating the routes and times where movement will not be interdicted. The proposed timeframe for evacuation was short, although it has now been extended by delays to the ground operation.

A policy to permanently drive Palestinians from Gaza would amount to ethnic cleansing and a war crime

Despite these measures, many civilians – as always in these cases – will choose to stay. Furthermore, in this specific context, many Palestinians fear that Israel is not trying to move them to a safe place, but instead trying to get them to vacate land which will be occupied and eventually settled. Palestinians fear that they will not be allowed to return. This is not the stated policy of the Israeli government. However, given Israel’s past conduct and the statements of several of its current ministers, this fear is understandable. It is also important to note that Israel has a history of valid tactical military justifications being instrumentalised by a minority within its cabinet to radically reshape its policy over time. This is how Operation Peace for Galilee in 1982, authorised by the Israeli cabinet to secure its northern border, was morphed in stages by Defence Minister Ariel Sharon into a siege of Beirut.

A policy to permanently drive Palestinians from Gaza would amount to ethnic cleansing and a war crime. It is therefore vital that, alongside support to Israel in defending itself, the international community is clear as to its expectations in confirming Israeli intent, and the consequences if that intent morphs into something illegal. One clear test is whether Israel will help to make the area to which people are evacuating safe by allowing food, medicine and clean water to be moved into southern Gaza.

It is also clear, however, that the international community will lack any credibility or authority on the issue if it simply demands a return to the status-quo ante. For many Palestinians, the progressive erosion of their control of the West Bank was choking off any prospect of a path to peace. For Israelis, the massacre conducted by Hamas on 7 October fundamentally changed their calculus. For years, Israel has been fearful as Iran and Hizbullah have consolidated their hold on Lebanon and Syria, amassing an arsenal of sophisticated weapons. In combination with the training and support to Hamas and the infiltration of Judea and Samaria, the IDF had come to view the status quo – amid increasing US disengagement from the region – as similarly unsustainable.

The IDF’s assessment today is that if the threat is left to expand, it will eventually threaten the viability of the Israeli state. Thus, their objective in the current conflict is not to simply inflict a dose of pain on Hamas to deter further fighting, but to systematically destroy its military capacity to conduct operations and thereby write down one of the threats. This risks Hizbullah intervening. But given that the Israeli security state fears things getting worse over time, many in the security establishment feel that if a fight must happen, then they would rather have it today.

For the international community, therefore, while deterring a regional escalation should be an objective, a mere temporary ‘stability’ is unlikely to look attractive to either side. If the international community wants long-term stability, it must be more proactively engaged in exploring a path to peace, rather than pursuing a systematic disengagement that simply cedes the region to Iran, which has characterised Washington’s approach for the last three years. There may emerge, from the ashes of this unfolding tragedy, an opportunity to build a new road to peace, just as there is the risk that the flames will engulf what remains of a rules-based international system that so many words have been pledged to defend.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.

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Dr Jack Watling

Senior Research Fellow, Land Warfare

Military Sciences

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