"Lenin and Stalin have evidenced their outstanding brilliance as mass leaders in every revolutionary requirement: in Marxian theory, political strategy, the building of mass organizations, and in the development of the mass struggle. The characteristic feature of their work is its many-sidedness. Both men of action as well as of thought, they have exemplified in their activities that coordination of theory and practice which is so indispensable to the success of the every-day struggles of the masses and the final establishment of socialism. Both have worked in the clearest realization of the twin truths that there can be no revolutionary movement without revolutionary theory, and that revolutionary theory unsupported by organized mass struggle must remain sterile."