How do we understand the Stalinist system (old USSR and similar formations) in historical-materialist terms? Was it a new kind of class society? Something halfway to socialism but ? A variety of fascism? Capitalist in everything but name? This session will include a brief overview of Marxist debates on "the Russian question," then focus on two analyses that took shape in the international Trotskyist movement in the 1940s. One was formulated by the Johnson-Forest Tendency in the US (named after the pseudonyms of its two most prominent theorists, C.L.R. James and Raya Dunayevskaya); the other, by Tony Cliff in Britain. Each characterized the USSR as a system of state capitalism. While agreeing in some ways, they framed different interpretations of when and how the workers' state turned into its opposite, and of what economic dynamics shaped Stalinism's development. These debates are not just of historical interest; they concern problems bound to reappear in future struggles.