In November of 1936, Haas joined the National Socialist party as an editor for the editorial board of the newspaper NSB. Because of his previous beliefs, he no longer believed in an international socialism, but a national socialism. When Germany invaded the Netherlands in 1940, he was promoted to editor in chief of De vakbewwging, which is the magazine NVV. This became the weekly newspaper for the SS in the Netherlands. Not only was he an editor, he was also the designer for the coin and money that the Netherlands released during the war.
Because of his position in the Socialist Party, De Haas was wanted for arrest after the war. Once he was arrested, De Haas managed to escape. He fled to Germany, before signing up for a French legion where he worked as a photographer. He was sent to French colonies such as Algeria and Vietnam. After this, he returned to Europe under a fake name. He died in 1995.
During the German occupation of the Netherlands, he was responsible for the design of the Dutch coins and paper money. He was also the chief editor of the weekly magazine of the Nederlandsche SS, called Storm during two periods i.e. from April 1941 until December 1942 and from September 1944 until May 1945.
Bogaard, Frank van den Een stoottroep in de letteren, 'Groot Nederland', de SS en de Nederlandse literatuur (1942–1944). Stichting Bibliographia Neerlandica, 's-Gravenhage, 1987. ISBN90-71313-07-7.
Groeneveld, Gerard Kriegsberichter, Nederlandse SS-oorlogsverslaggevers 1941–1945. Uitgeverij Vantilt, Nijmegen, 2004, pp. 305–317. ISBN90-77503-09-9
Groeneveld, Gerard Zwaard van de geest, het bruine boek in Nederland 1921–1945. Uitgeverij Vantilt, Nijmegen, 2001. ISBN90-75697-51-1.
