With the rise of China and Russia, the international system is poised to shift from unipolarity to multipolarity. This article argues that this structural reconfiguration will have—and is having—a profound effect on the future efficacy of the responsibility to protect (R2P). The rise of R2P, we argue, must be situated in the context of the end of the Cold War and the ‘unipolar moment’ this heralded. The efficacy of R2P is predicated on the assumption that moral advocacy can influence liberal democracies to re-orientate their foreign policy priorities towards human rights protection. We argue that the emerging multipolarity will expose the temporal specificity of this strategy and, ultimately, weaken the influence of R2P.