This article seeks to explain both the continuity and the changes in US grand strategy since the end of the Cold War by adopting a critical political economy approach that focuses on the social origins of grand strategy-making. Systematically seeking to link agency and structure, we analyse how grand strategy-makers operate within given social contexts, which we define in terms of, on the one hand, elite networks within which these actors are embedded, and, on the other hand, the international structural context in which the US is positioned. After reviewing the grand strategies as pursued by the Clinton, Bush and Obama administrations, and relating them to the structural context in which they evolved, we proceed by offering a Social Network Analysis in which we compare the networks of key officials of the three administrations in terms of: (1) their corporate affiliations, and (2) their affiliations to so-called policy-planning institutions. On this basis we argue that the continuities of post-Cold War US grand strategy — which we interpret as reproducing America’s long-standing ‘Open Door’ imperialism — can be explained in terms of the continuing dominance of the most transnationally oriented sections of US capital. Second, we show that, this continuity notwithstanding, there is significant variation in terms of the means by which this grand strategy is reproduced, and argue that we must explain these variations not only in terms of the continuously changing global context, but also as related to some significant differences in affiliation with the policy-planning network.