This book grew from a paper I wrote for INTERIGHTS shortly after the September 11 attacks. The paper was motivated by the apparent marginalisation of the issue of legality in public discourse on responses to those attacks, and the surprising dearth of legal material published in their immediate aftermath. In the void where there should have been debate on which responses would serve the interests of international justice, peace, security and the rule of law, the confusion and need for clarification of legal issues grew. I was encouraged by those who used that paper in their work, including partner organisations in the many countries in which INTERIGHTS works, to publish an expanded piece that addresses additional aspects of the legal framework and considers it alongside the practice of the ‘war on terror’ since 11 September 2001.

Since then, international lawyers have become more vocal and there is certainly more published material. International law is no longer absent from political discourse on the ‘war on terror’, and indeed there may be a newfound alertness to issues of international legality in public debate that is in many respects promising. However at times it seems that there is greater confusion than ever, and with it an increased vulnerability in the international legal order. This book hopes to contribute to addressing the confusion, and the perception of legal vacuum. It is written from the perspective of a practitioner in the field of human rights and international criminal law, where international law, its legitimacy and standing, are essential tools not only to combat terrorism but to guard against future human rights abuse in other contexts.