Historically, the central themes in American conservatism have included respect for American traditions, support of republicanism and the rule of law, Judeo-Christian values, anti-Communism, advocacy of American exceptionalism and a defense of Western civilization from perceived threats posed by moral relativism, multiculturalism, and postmodern ridicule of traditional culture. Liberty is a core value, with a particular emphasis on strengthening the free market, and opposition to high taxes and government or labor union encroachment on the entrepreneur.