Bill Browder, founder and CEO of the hedge fund Hermitage Capital Management, discussed Russia and Vladmir Putin with TheStreet's Rhonda Schaffler at the Aspen Ideas Festival in Aspen, Colorado. Browder is the author of 'Red Notice,' a book that examines corruption in Russia, and the killing of the hedge fund's lawyer Sergei Magnitsky while in custody in a Moscow prison. Browder was once the largest single foreign investor in Russia, but he regrets investing there and what subsequently happened. 'In my situation, first we made made money in Russia. Then they tried to take our money away,' said Browder. 'And then they committed a terrible corruption crime connected to our companies. And then they killed my lawyer, Sergei Magnitsky, after torturing him to death. So if I could turn back the clock, I'd rather have none of that to avoid the death of Sergei Magnitsky.' Browder said Putin is 'the single greatest threat to world peace and U.S. national security.' He says Putin's military prowess serves as a diversion to the problems in Russia, such as a weak economy and a falling ruble.