Cosmopolitanism and nationalism are often presented in binary terms, as standing in opposition to each other, especially with regards to education. In this paper, we establish a framework for studying education policy today through the lens of a concept we have developed: 'cosmopolitan nationalism'. Many education systems around the world are grappling with and simultaneously integrating both cosmopolitan and nationalist elements in policy objectives, curricular content and pedagogic approaches. Through an in-depth analysis of three country examples -- China, the US and Israel -- we outline four different manifestations of education policy that can be explained by employing the analytical lens of cosmopolitan nationalism: (i) the increasing prominence and visibility of the International Baccalaureate within these three public education systems; (ii) reforms of specific curricula elements and pedagogies legitimised with reference to approaches assessed as globally leading through international assessments; (iii) efforts to promote national education systems as international beacons of best practice; (iv) creation of alternative education provisions that are promoted globally for very specific purposes and populations. We argue that, given our heterogeneous sample of case study countries, and careful analysis of these, a cosmopolitan nationalism lens offers important insights into education policy-making today which has the potential to be applied in other contexts.