How was radio, film, and print advertisements/posters successfully exploited by political leaders (Mussolini, Hitler, Churchill, Roosevelt, and Stalin) of the 1920s and 1930s? What role did propaganda play? What were the outcomes of this exploitation?

How was radio, film, and print advertisements/posters successfully exploited by political leaders (Mussolini, Hitler, Churchill, Roosevelt, and Stalin) of the 1920s and 1930s? What role did propaganda play? What were the outcomes of this exploitation?