In recent years Canadian government has promoted concept of an international responsibility (R2P) populations from genocide, ethnic cleansing, and other similar politically induced humanitarian catastrophes. This political effort seemed meet success at 2005 world summit, where community of states affirmed in outcome document a commitment to take collective action, in a timely and decisive manner, through security council, in accordance with charter, including chapter VII, on a case-by-case basis and in cooperation with relevant regional organizations as appropriate, should peaceful means be inadequate and national authorities manifestly fail protect their populations from genocide, war crimes, ethnic cleansing, and crimes against humanity.1 While this adoption of R2P has been hailed by UN officials, some governments, international lawyers, and human rights organizations as a landmark development in international society, responsibility doctrine continues generate debate, scepticism, and anxiety from several perspectives. The most controversial implication of R2P is its potential broaden justifications for use of force by states, beyond self-defence and maintenance of international peace and security, include protection of vulnerable populations.Why should concept and practice of humanitarian intervention-defined narrowly here as use of force by states for purpose of human protection-remain so controversial? The United Nations, founded in shadow of two world wars, considered its highest priority be maintenance of international peace and security, a mandate that required strict prohibitions against use of force between states. During Cold War, states offered humanitarian reasons as official justifications for uses of force, even in those cases where use of force succeeded in stemming mass atrocities.2 With end of Cold War, some western leaders began embrace idea of humanitarian intervention, partly as a way convey a transformed, more cooperative, and purposive international society no longer constrained by geopolitical struggles of Cold War. Humanitarian interventions would constitute global law enforcement, implying disinterested and impartial use of force in service of universal humanitarian interests. The appeal of idea, however, was not confined western leaders. In supporting United Nations security council resolution 794 authorizing use of force in Somalia in 1992, for example, various African ambassadors talked of the universal being aroused by desperate plight of Somalis.3Unfortunately, having a conscience does not automatically translate into having a sound political or military strategy; UN's and US's mistakes and failures in Somalia generated disillusionment and wrong lessons that would haunt international community's dismal response 1994 Rwandan genocide. More than a decade after that particular failure of humanity, we live in a world in which mass atrocities can continue essentially unabated for years.4 It is disturbing think that instead of a world in which crimes against humanity never again occur, we have a world that is resigned indiscriminate bombing, burning, organized raping, and killing as ever again features of global background, not mention millions of deaths that result from severe global poverty. The persistence of inhumanity unfolding in places such as Darfur region in Sudan means that practice of humanitarian intervention is sure remain a live debate among intellectuals, activists, policymakers, and various publics.Given contemporary global conditions, what constitutes moral and political significance, potential, and limits of R2P doctrine? In what follows, I aim examine realist and idealist critiques of R2P and of humanitarian intervention as they have developed since early 1990s. …