Why has Indian foreign/security policy been characterized by drift from time to time? Neoclassical realism offers a useful but incomplete way of explaining the phenomenon of suboptimal policy outcomes. It shows how material factors working at the domestic level prevent states from responding adequately to systemic incentives. The present study finds that a materialist explanation – the distribution of domestic political power – is useful in explaining policy drift in two cases (the India-US nuclear deal and the India-Sri Lanka ‘non-deal’). In two others (the formulation of nuclear strategy and the response to cross-border terrorism), policy drift has not been caused so much by material factors as by a “responsibility deficit,” i.e. the lack of political commitment on the part of policy makers. The overarching argument is that neoclassical realism would gain explanatory power from integrating a normative element into its analytical framework.