The attacks of 9/11 spurred the international community to elevate extreme political violence to a threat to international peace and security. For the United Nations (UN) issues of "enforcement" were centre stage in the response, alongside state capacity-building and a unique ongoing role for the Security Council in the domain of counter-terrorism. With the excesses of the U.S.A. "war on terror', the response of civil society and many states has challenged the relevance and legitimacy of the UN, leading to the development and 2006 adoption by all states of a broad-based Global Counter-Terrorism Strategy. This paper examines the development and limitations of action by the Security Council and reviews the launch of a UN strategy billed as the basis for a "principled and effective" response to terrorism. The prospects of success are reviewed with reference to the adoption of UN norms, the funding of state capacity building and the continued need for Security Council reform.