On August 23, 1951, Wisner succeeded Allen W. Dulles and became the second Deputy Director of Plans, with Richard Helms as his chief of operations. In this position, he was instrumental in supporting pro-American forces that toppled Mohammed Mossadegh in Iran in 1953 and Jacobo Arbenz Guzmán in Guatemala in 1954. Another project he was involved in was with regard to the Belarus Brigade's leaders, a unit incorporated into a German SS division, who were assisted into the United States after the Second world war, due largely to his efforts. In defiance of federal law, John Loftus asserted, the Office of Policy Coordination helped obtain visas for Nazi collaborators from Belarus — who were believed to have facilitated numerous atrocities by the Nazi Germany. According to Loftus, it was all part of a Cold War scheme to wage guerrilla warfare in Soviet-occupied Europe, in which the Nazi collaborators were to play a key role. When the project collapsed, however, the Belarussians quickly settled in and obtained US citizenship – and intelligence agencies protected them from exposure for decades.