This article contributes to the development of state capitalism as a reflexively critical project focusing on the morphology of present-day capitalism, and particularly on the changing role of the state. We bring analytical clarity to state capitalism studies by offering a rigorous definition of its object of investigation, and by demonstrating how the category state capitalism can be productively construed as a means of problematising the current aggregate expansion of the state’s role as promoter, supervisor and owner of capital across the world economy. Noting some of the geographical shortcomings of the field, we outline an alternative research agenda ‘uneven and combined state capitalist development’ which aims at spatialising the study of state capitalism and revitalising systemic explanations of the phenomenon. Rather than the negation of an abstract model of free-market capitalism, or the rise of a nationally scaled variant of capitalism, we posit contemporary state capitalism as a global process of restructuring of the capitalist state (including in its liberal form) underpinned by secular transformations in the materiality of surplus-value production, such as the consolidation of new international divisions of labour driven by automation and labour-saving technologies. The political mediation of these transformations results in the combined expansion of state-capital hybrids and of muscular forms of statism, which develop in inter-referential and cumulative forms across territory, producing further state capitalist modalities. This is a particularly potent dynamic in contemporary state capitalism, and its tendency to develop in a spiral that both shapes and is shaped by world capitalist development.