Is Intellectual Property Law a Threat to Capitalism?

A thoughtful, worthwhile piece today from FunctionalAmbivalent on whether intellectual property law is going too far. An excerpt:

The purpose of patent protection, as laid-out in the Constitution, is promoting progress, not stifling it. By allowing companies to patent basic ideas like one-click ordering — rather than the underlying technology that makes one-click possible — we’re guaranteeing that improvements will reach consumers more slowly. It’s not, after all, possible for Amazon’s competitors to come up with a “zero click” technology.

There may not be a better example of how ridiculous this is getting than Netflix’ suit against Blockbuster.