There has been a connection between Atheism and terrorism over history. Many argue that Darwinism and the idea of the "survival of the fittest", has inspired racism, Nazism, communism and terrorism. Robert Pape of the University of Chicago points out that the Tamil Tigers, a Sri Lankan terrorist group who are responsible for more suicide bombings over the last two decades than even Al Quaeda, are heavily influenced by a Marxist/Leninist ideology which is atheistic. Many atheist despots of the 20th century, namely Joseph Stalin and Mao Zedong can be accused of terrorist acts in their attempt to create a religion-free utopia.