The developments in the LOAC [law of armed conflict] have now made it very difficult for a commander to conduct a siege that is both successful and lawful.
Siege warfare has been employed throughout the ages and remains dramatically relevant today. Reports of civilians forced to eat grass to survive in Homs, living underground to escape bombardments in Eastern Ghouta and targeted by Islamic State of Iraq and Syria as they seek to flee eastern Mosul join similarly harrowing stories from Grozny and Sarajevo.
Armed forces resort to sieges for a variety of purposes. Often sieges are used to compel enemy forces to surrender, and to gain control of an area while avoiding fighting in urban areas. But they can also be a way of containing enemy forces in a particular location, so that such forces do not impede military operations elsewhere.
Questions of the compatibility of sieges with modern rules of international humanitarian law (IHL) arise when besieged areas contain civilians as well as enemy forces
Questions of the compatibility of this practice with modern rules of international humanitarian law (IHL) arise when besieged areas contain civilians as well as enemy forces. This briefing addresses those rules of IHL that are particularly relevant to sieges. The paper does not, however, purport to settle all of the difficulties that arise in the application of the law to sieges or to deal in detail with all of the relevant legal issues. In addition to IHL, international human rights law continues to apply in armed conflict; states have obligations regarding persons over whose enjoyment of rights they exercise power or effective control.