'The Chatham House Principles on the Use of Force in Self-defence' sought to clarify developments in the law on this aspect of the use of force post 9/11. Controversy remains as to whether the law adequately meets the challenge of threats from non-state actors. As for mass atrocities, to what extent does the law authorise the use of force to prevent such egregious human rights violations: what has been the legal impact of the Responsibility to Protect doctrine? What can be done to ensure compliance with the existing legal framework on the use of force, to clarify UN peacekeeping mandates and to ensure effective and fair use of other conflict prevention tools such as sanctions?
As for the legal landscape that governs the manner in which wars are fought, this has changed rapidly in the last decade. The 'Human Rights in Armed Conflict' project produced practical guidance on how international human rights law applies to armed forces when conducting military operations overseas. International humanitarian law faces a number of challenges, both in the application of the law and its enforcement; we are examining these challenges with key actors such as the ICRC.
A particular area of focus is the principle of proportionality in any military attack where we are seeking to clarify the civilian (‘collateral damage’) element of this fundamental principle of international humanitarian law.