SH: Pomo is rhetoric-heavy, yes. But rhetoric is a tool, so one can ask how it’s being used and why it’s being used that way. The postmodernists have rejected reason, and along with it concern for evidence and consistency. What then is the purpose of rhetoric? In pomo practice, there are a couple of possibilities.
One is that rhetoric becomes a kind of subjectivist expressionism - you play around with language and hope that something interesting pops out. Derrida is often like this - I think of him as a performance artist of postmodernism. In its darker moods, this approach recalls a line from Kate Ellis, a sympathetic-to-postmodernism commentator, who noted “the characteristically apolitical pessimism of most postmodernism, by which creation is simply a form of defecation.” Whatever’s been processing and churning up inside you - you just let ‘er rip.
The other use of rhetoric is politically-charged persuasion. Pomo rhetoric becomes long on emotionalism, ad hominem, and so on, and it becomes short on logic and evidence. But the point of such rhetoric is effectiveness, not truth.
You mention that much pomo political rhetoric is anti-capitalist and champions unlikely causes such as fundamentalist Islam. Here the pomo are taking a page out of Lenin’s and Marcuse’s playbooks. There’s a long-ish story here that I talk about in Chapter 5 of Explaining Postmodernism: Traditional Marxism said that capitalism would collapse from the inside (the exploited and alienated workers would rise); but when that didn’t happen, Marxists theorized that capitalism had exported its misery to the Third World (Lenin’s idea) or to outcast and marginalized subcultures (Marcuse’s idea). So the new strategy was to cultivate the anti-capitalist resistance in those places.
Like other pomo of this generation, Žižek is an evolving combination of the above.
Go read the entire interview. And check out the book:
UPDATE: Now here is a perfect example of the kind of rhetoric designed to end debate that is so typical of today's left, "Barney Frank's Namecalling":
Barney Frank’s attack on Justice Scalia as a “homophobe” is inane at several levels:
First, the term “homophobe” is an ugly epithet designed to stigmatize (“he’s the sicko”) those who don’t embrace the homosexual agenda. It’s intended to cut off serious discussion, not to promote it. It doesn’t belong in public discourse.
Second, Frank uses his epithet in the course of expressing his concern that a Supreme Court that includes Scalia might not strike down the federal Defense of Marriage Act. The Defense of Marriage Act was approved by overwhelming majorities in each House of Congress (85-14 in the Senate, 342-67 in the House) in 1996 and signed into law by President Clinton. Senators in favor of DOMA included Biden, Bradley, Daschle, Kohl, Leahy, Levin, Lieberman, Mikulski, Murray, Reid, Sarbanes, and Wellstone. Millions and millions of voters in state after state have acted to preserve traditional marriage. Does Frank regard all these Americans as “homophobes”?
Third, Scalia’s position is clear: The Constitution does not address the matter of same-sex marriage. Therefore, the political processes are free to decide whether or not to adopt it. He, as a justice, will defer to the political processes, whatever the result. In other words, on this matter as on so many more, Scalia will not indulge his own policy preferences (whatever they are) and will not write those preferences into the Constitution. Frank wants liberal activist justices who will indulge his and the Left’s own policy preferences on homosexual matters (and so much more). That’s his real beef with Scalia, and he’s masquerading it under the “homophobe” label.
I’ll leave to others whether Frank’s name-calling is a tactic designed to distract attention from his role in causing the ongoing financial crisis.
In fact, this is precisely how postmodern rhetoric works so brilliantly--to distract from real issues and a rational discussion of them; and to demonize anyone who dares to criticize any political policy that the left promotes. Those who dare oppose them (or, in this case, not actively support them) are always "racist", "sexist", "homophobic" etc. etc. Hence, we can't have a rational discussion in this country anymore about abortion, Gay marriage, or any policy like National Health Care (those who oppose that "want poor people to die or suffer") and so on. The idea that there might be reasonable concerns or consequences that accrue socially or culturally from these policies--intended or unintended--is completely alien to the left's mindset. It's all part of the idea that SC&A have explained many times, the left is of the opinion that they are better people and aren't nearly as concerned about finding better ideas as much as they are with proving to you how superior they are.