I think this an image with impact because represent the victory of the Soviets over the Nazis and the end of the second world war, ending with the most bloody war in the history, but also represent the war of power between Soviet Union and United States, the war of who have the best economic system, United States with the capitalism and the Soviet Union with the communism.

image link: Reichstag_flag_original.jpg (372×268) (wikimedia.org)