 During World War II as an ardent anti-communist he sided with the Axis powers and the Russian Liberation Movement, and briefly served in the propaganda services of the Wehrmacht as head of the Russian section.In early 1945 he returned to active front-line service as a Major in Boris Smyslovsky's 1st Russian National Army.Through Liechtenstein Messner and his family moved in 1947 to Argentina, where he continued his earlier work as a journalist, publisher, writer and military theorist.