Political philosophy is the study of such topics as politics, liberty, justice, property, rights, law, and the enforcement of a legal code by authority: what they are, why (or even if) they are needed, what, if anything, makes a government legitimate, what rights and freedoms it should protect and why, what form it should take and why, what the law is, and what duties citizens owe to a legitimate government, if any, and when it may be legitimately overthrown, if ever. In a vernacular sense, the term "political philosophy" often refers to a general view, or specific ethic, political belief or attitude, about politics that does not necessarily belong to the technical discipline of philosophy. In short, political philosophy is the activity, as with all philosophy, whereby the conceptual apparatus behind such concepts as aforementioned are analyzed, in their history, intent, evolution and the like.
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 Hannah Arendt, 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.
Communism remained an important focus especially during the 1950s and 1960s. Colonialism and racism were important issues that arose. In general, there was a marked trend towards a pragmatic approach to political issues, rather than a philosophical one. Much academic debate regarded one or both of two pragmatic topics: how (or whether) to apply utilitarianism to problems of political policy, or how (or whether) to apply economic models (such as rational choice theory) to political issues. The rise of feminism, LGBT social movements and the end of colonial rule and of the political exclusion of such minorities as African Americans and sexual minorities in the developed world has led to feminist, postcolonial, and multicultural thought becoming significant. This led to a challenge to the social contract by philosophers Charles W. Mills in his book The Racial Contract and Carole Patemen in her book The Sexual Contract that the social contract excluded persons of colour and women respectively.
In Anglo-American academic political philosophy, the publication of John Rawls's A Theory of Justice in 1971 is considered a milestone. Rawls used a thought experiment, the original position, in which representative parties choose principles of justice for the basic structure of society from behind a veil of ignorance. Rawls also offered a criticism of utilitarian approaches to questions of political justice. Robert Nozick's 1974 book Anarchy, State, and Utopia, which won a National Book Award, responded to Rawls from a libertarian perspective and gained academic respectability for libertarian viewpoints.
Contemporaneously with the rise of analytic ethics in Anglo-American thought, in Europe several new lines of philosophy directed at critique of existing societies arose between the 1950s and 1980s. Most of these took elements of Marxist economic analysis, but combined them with a more cultural or ideological emphasis. Out of the Frankfurt School, thinkers like Herbert Marcuse, Theodor W. Adorno, Max Horkheimer, and Jürgen Habermas combined Marxian and Freudian perspectives. Along somewhat different lines, a number of other continental thinkers—still largely influenced by Marxism—put new emphases on structuralism and on a "return to Hegel". Within the (post-) structuralist line (though mostly not taking that label) are thinkers such as Gilles Deleuze, Michel Foucault, Claude Lefort, and Jean Baudrillard. The Situationists were more influenced by Hegel; Guy Debord, in particular, moved a Marxist analysis of commodity fetishism to the realm of consumption, and looked at the relation between consumerism and dominant ideology formation.
Another debate developed around the (distinct) criticisms of liberal political theory made by Michael Sandel and Charles Taylor. The liberal-communitarian debate is often considered valuable for generating a new set of philosophical problems, rather than a profound and illuminating clash of perspectives.
There is fruitful interaction between political philosophers and international relations theorists. The rise of globalization has created the need for an international normative framework, and political theory has moved to fill the gap.
One of the most prominent subjects in recent political philosophy has been the theory of deliberative democracy. The seminal work is by Jurgen Habermas in Germany but the most extensive literature has been in English, led by theorists such as Jane Mansbridge, Joshua Cohen, Amy Gutmann and Dennis Thompson.