Why are pharma drugs so expensive? (Redux)

As a follow up to an earlier post, find the following Reason Hit and Run dispatch, and a lively comments section.

The gist? Is the U.S. government just a "large buyer" of anything? And should it be a large buyer of drugs? And, as our earlier post alluded, if drug companies are not allowed the protection of long patents, will they be willing to make large R & D expenditures for other, potentially life-saving drugs?