On 20 June 1923, Karl Radek gave a speech before the Comintern in which he proposed a common front with the Nazis in Germany. However, the two radicalisms were mutually exclusive and they later become profound enemies. However, fascism and communism have common positions in their opposition to liberalism, capitalism, individualism and parliamentarism. Fascists and communists also agree on the need for violent revolution to forge a new era. While fascism is opposed to Bolshevism, both Bolshevism and fascism promote the one-party state and the use of political party militias. Fascism denounces democratic socialism as a failure. Fascists oppose it for its support of reformism and the parliamentary system that fascism reject. However, social democracy, similar but less socialist than democratic socialism, was denounced by Joseph Stalin and Grigory Zinoviev as a variant of fascism—"social fascism"—and that designation became the "official ideology of the world Communist movement. Stalin described fascism and social democracy as "twin brothers". Italian Fascism had ideological connections with revolutionary syndicalism, in particular Sorelian syndicalism. The Italian Fascist regime officially acknowledged revolutionary syndicalist Georges Sorel—along with Hubert Lagardelle and his journal "Le Mouvement socialiste"—as major influences on fascism. According to Sternhell, "most syndicalist leaders were among the founders of the Fascist movement" and that by the mid-1920s "many even held key posts" in the Fascist regime. The Sorelian emphasis on the need for a revolution based upon action of intuition, a cult of energy and vitality, activism, heroism and the utilization of myth was utilized by fascists. Many prominent fascist figures were formerly associated with revolutionary syndicalism, including Mussolini, Arturo Labriola, Robert Michels, Sergio Panunzio and Paolo Orano.