Debates over the implications of China’s rise for global governance have reached an impasse, since evidence exists to support both ‘revisionist’ and ‘status-quo’ intentions. This means that neither is strictly falsifiable and hence the debate, as currently structured, is irresolvable. However, contradictions are explicable if we recognise that China is not a unitary state. Since the beginning of the reform era, its international engagements have been shaped by the uneven transformation – fragmentation, decentralisation and internationalisation – of state apparatuses. Contradictory international actions thus may reflect not top-down strategic direction, but conflicts, disagreements and coordination problems within China’s transformed party-state. Our state transformation approach directs us away from evaluating China’s approach to global governance in toto – whether it is overall a revisionist or status quo power – towards a detailed analysis of particular policy domains. This is because in each issue-area we find different constellations of actors and interests, and varying degrees of party-state transformation. We demonstrate the centrality of state transformation analysis for explaining the co-existence of revisionist and status quo behaviours through the apparently hard test case of nuclear technologies. Even in this ‘high politics’ domain, state transformation dynamics help explain China’s inconsistent international behaviours.