Who was the most successful Soviet spy involved in the Manhattan Project ?
1931 ) confessed member of the Ware group of communists who engaged in espionage for the USSR in Washington , D.C. ; after leaving the party , he became a conservative and avowed anti-communist Harry Dexter White — alleged Soviet spy who spearheaded the creation of the World Bank and the International Monetary Fund ; later revealed allegedly to have been involved with the Silvermaster and Ware groups of communist spies while he was a senior U.S. Treasury official in the Franklin D. Roosevelt and Truman administration Flora Wovschin — alleged Soviet spies as revealed in the Venona project