Hoffman has worked on the projects of neo-Nazi Tom Metzger and of the Holocaust deniers Willis Carto, David Irving, Ernst Zündel, and Herman Otten. Hoffman was the Assistant Director of the Institute for Historical Review (!HR), a Holocaust denial organization for a period. He retains a connection with it. Stephen A. Atkins, in his book, "Holocaust Denial as an International Movement" (2009), wrote that Hoffman's newsletter "Revisionist History" promotes Holocaust denial and Hoffman contends that "the real Holocaust of World War II was deaths caused by the Allies." He quotes Hoffman denying the existence of gas chambers: