Read this: From the end of World War II until 1971, when John Rawls published A Theory of Justice, political philosophy declined in the Anglo-American academic world, as analytic philosophers expressed skepticism about the possibility that normative judgments had cognitive content, and political science turned toward statistical methods and behavioralism. In continental Europe, on the other hand, the postwar decades saw a huge blossoming of political philosophy, with Marxism dominating the field. This was the time of Jean-Paul Sartre and Louis Althusser, and the victories of Mao Zedong in China and Fidel Castro in Cuba, as well as the events of May 1968 led to increased interest in revolutionary ideology, especially by the New Left. A number of continental European émigrés to Britain and the United States—including Karl Popper, Friedrich Hayek, Leo Strauss, Isaiah Berlin, Eric Voegelin and Judith Shklar—encouraged continued study in political philosophy in the Anglo-American world, but in the 1950s and 1960s they and their students remained at odds with the analytic establishment.

What immigrants to the US and Britain encouraged studies in Marxism?
What is the answer? (If it cannot be answered, return "unanswerable")
unanswerable