Two recent posts in the recent joint blog series on international law and armed conflict concluded that the siege of a defended locality was permitted under the Law of Armed Conflict (LOAC)/International Humanitarian Law (IHL), but subject to a series of constraints regarding the protection of civilians. The prohibitions on starvation of civilians (in Geneva Conventions Additional Protocol I Art 54, Additional Protocol II Art 14 and in customary law, applicable both to international and non-international armed conflicts) were in particular analysed in Gloria Gaggioli’s excellent post. Given that ‘the prohibition of starvation as a method of warfare does not prohibit siege warfare as long as the purpose is to achieve a military objective and not to starve a civilian population’ (ICRC Customary IHL database, Rule 53), she notes that it is in practice very difficult to prove that the purpose of a siege is the starvation of civilians. However, she goes on to argue, persuasively, that if a siege can be construed as an ‘attack’ the proportionality rule would apply, thereby requiring any incidental starvation of civilians to be assessed against the concrete and direct military advantage anticipated.
As starvation is so central to much of the suffering inflicted on civilian populations in today’s city sieges in the Middle East, I want to return to the question of whether starvation of civilians needs to be the purpose (or even a purpose) of a belligerent to fall within the prohibition and whether incidental starvation may be lawful (if it is not disproportionate), by way of offering some thoughts as to what a legal analysis of the purpose of the relevant siege tactics might look like. If the prohibition on the starvation of civilians was in practice reduced to a prohibition on excessive starvation of civilians, this would obviously severely restrict the protection offered by Art 54 API and Art 14 APII.
We need to ask, firstly, what is the actual conduct denoted by the term ‘siege’ and, secondly, what is the military objective to which starvation of civilians is incidental?
Methods of warfare denoted by ‘siege’
How a siege might be characterised in legal terms – as an ‘attack’, a ‘‘method’ of warfare, a ‘course of conduct’ and so on – is complicated by the fact that the term ‘siege’ is defined neither in IHL nor in contemporary military doctrine. (‘Siege warfare is almost completely absent from current US military doctrine’, observe Beehner, Berti and Jackson, for example.) Recent or ongoing city sieges have often been described as ‘medieval’ to emphasise their brutality, but that encourages a view of the siege that is at least 500 years out of date. Today’s sieges are typically laid using jet aircraft, focus on sprawling conurbations without city walls, and are undertaken for purposes of counter-insurgency rather than conquest.
Unpacking what is meant by ‘siege’, we can identify three sets of tactics, each employing distinct methods of warfare, which are often confused:
- Isolating enemy forces by cutting off their access to reinforcements (or their ability to reinforce others) and cutting or degrading communications;
- Encircling an entire locality, using a line of fortification to control entry/exit (in traditional sieges known as circumvallation but now in the urban context more often referred to as a ‘ring of steel’); this makes isolation more complete and concentrates enemy forces, making them more vulnerable to attack;
- Blocking or barring the passage of supplies, either selectively or completely, preventing fuel, food and other essential commodities, from entering or leaving. (In the military literature this is often referred to as a ‘blockade’ but that risks confusion with the use of the term under international law which specifically denotes a naval blockade.)
These tactics are essentially cumulative; isolation of an enemy does not automatically imply, for example, a block on the passage of essential commodities. Thus the siege of Sadr City in Baghdad by US and Iraqi forces during the Iraq war employed neither encirclement nor a block on essential commodities, relying on partial isolation and targeted operations to degrade the capacity of the Jaish al-Mahdi. In a recent paper on ‘The Reemergence of the Siege’, a veteran of Operation Inherent Resolve (the US-led coalition military operation against ISIS in Iraq and Syria) observes that ‘[t]he modern siege is not necessarily characterised by a [land] blockade, but more by an isolation of an adversary through encirclement while maintaining sufficient firepower against the besieged to ensure steady pressure.’ The logic of these developments becomes readily apparent when one considers not only the humanitarian implications of a block on essential commodities but also the modern urban context – hermetically sealing a modern city is near impossible and, while vulnerable civilians suffer, defending forces will be able to control and use the means of survival that remain or can be grown.
Once we break the assumption that starvation is inherent in the notion of siege, the argument that because sieges are not explicitly prohibited by IHL, starvation tactics may therefore in certain circumstances be lawful, requires further scrutiny. Rather than benefiting from some general customary law permission attendant on the term ‘siege’, the specific methods of warfare employed, in this case a block on essential commodities, need to be assessed for IHL compliance.
Starvation as a method of warfare
Let us take the following scenario (hypothetical, but no doubt familiar). Government forces encircle a city controlled by insurgents and impose a block on essential commodities which threatens the population with starvation. They argue that they have not violated Art 14 APII (‘Starvation of civilians as a method of combat is prohibited …’) as their action is justified by the military objective of putting pressure on the city’s insurgent fighters, and that it is the insurgents who are preventing civilians from leaving the city.
The terse wording of the prohibition on starvation of civilians appears to allow of no exceptions, and unlike other provisions of the Geneva Conventions and Additional Protocols, for example those concerned with evacuation or displacement of civilians, there is no exception for ‘imperative military reasons’ (see GC IV Art49, APII Art17(1)). However, because the prohibition is not of starvation of civilians tout court but starvation as a method of combat (Art 54 API has ‘method of warfare’) it has been suggested that conduct is only prohibited where starvation of civilians is its purpose. Thus the UK Joint Service Manual of the Law of Armed Conflict cautions that ‘The law is not violated if military operations are not intended to cause starvation but have that incidental effect’ (5.27.2), giving as one example the cutting off of enemy supply routes which are also used for transportation of food.
Could this exception apply to the case of a city-wide block on essential commodities? At least where it is considered an ‘attack’ (an interpretation arguably supported by the use of the word ‘combat’), such conduct cannot by nature be directed against a specific military target, it affects fighters and civilians without distinction, and should therefore be considered unlawful because it is indiscriminate. It is precisely to mitigate the indiscriminate effect of such operations that IHL provides for humanitarian access and/or evacuation of the civilian population.
If for the moment we nonetheless suppose that incidental starvation of civilians might in certain circumstances be lawful, we need to ask: what is the legitimate method of warfare to which it is incidental? The Department of Defense Law of War Manual provides a blunt answer: ‘It is a legitimate method of war to starve enemy forces’ (5.20.1). In the hypothetical scenario above, the government’s case would seem further supported by the fact that the evacuation is here being prevented by the insurgents themselves. As stated in the UK military manual: ‘…so long as the besieging commander left open his offer to allow civilians and the wounded and sick to leave the besieged area, he would be justified in preventing any supplies from reaching that area’ (5.34.3).
This justification is linked to the objective of ‘prevent[ing] food as well as other supplies from reaching the defending troops’. This may appear a legitimate method of warfare if the object of the siege is a building or a neighbourhood, but is it possible to deny insurgent fighters access to food through blocking passage of essential commodities to a city of 200,000, 500,000 or one million people? Both common sense and recent experience would suggest not. (Indeed, the operation of a block on commodities under such circumstances has often in recent times perversely benefited the insurgents by enabling them to profit from selling contraband.) In this case, the method of warfare chosen would seem to fail the basic test stipulated by American Military Tribunal in the WWII Hostage case: ‘There must be some reasonable connection between the destruction … and the overcoming of the enemy forces’ (pp. 1253-4).
I would argue that the city-wide block on commodities in our hypothetical case above is unlawful not just because the starvation of civilians is a result, and one achieved through a method of warfare that is by its nature indiscriminate, but additionally because the method of warfare chosen is incapable of bringing about the military objective of starving enemy forces. There is no reasonable connection between a city-wide block on entry of essential commodities and the overcoming of the enemy forces.
Mass starvation under siege in the Middle East may mark the revival of an old scourge of war, but IHL requires it to be assessed as a specific method of warfare in the light of contemporary urban conflict. The Diplomatic Conference that agreed the 1977 Additional Protocols did not intend to ban sieges but rather to impose humanitarian restrictions realistic to the modern practice of siegecraft. To allow widespread ‘incidental’ starvation of civilians in relation to some ill-defined military objective would be to defeat one of the most important of those restrictions.
In fact, numerous reports by the UN Commission of Inquiry on Syria and other UN mechanisms have found that the purpose of many blocks on food and other essentials in Syria as elsewhere in the Middle East has been the collective punishment of the civilian population for perceived support of the insurgency and/or an attempt to force the displacement of civilians from areas held by the insurgents, conduct which is clearly prohibited by IHL. This was recognised last year in Security Council Resolution 2417 which reiterated the unambiguous condemnation of ‘the use of starvation of civilians as a method of warfare in a number of conflict situations’.