As a small child with his mother in Saint Petersburg , Bers had cheered the Russian Revolution and the rise of the Soviet Union , but by the late 1930s he had become disillusioned with communism after the assassination of Sergey Kirov and Stalin 's ensuing purges . His son Victor later said that " His experiences in Europe motivated his activism in the human rights movement , " and Bers himself attributed his interest in human rights to the legacy of Menshevik leader Julius Martov . He founded the Committee on Human Rights of the National Academy of Sciences , and beginning in the 1970s worked to allow the emigration of dissident soviet mathematicians including Yuri Shikhanovich , Leonid Plyushch , Valentin Turchin , and David and Gregory Chudnovsky . Within the U.S. , he also opposed the American involvement in the Vietnam War and southeast Asia , and the maintenance of the U.S. nuclear arsenal during the Cold War
purges
Great Purge
Lipman Bers