A recent article, pointed out by Stupid Git, mentions that the commission probing the 2001 attacks has asked Cheney to tell them what info he had pointing to an Iraq--Al-Qaida link. Since they've been allowed to see all of the classified info, it'll be interesting to find out what other sources Cheney had. Perhaps he had a direct revelation from God. Or maybe he's really a Theosophist and is channeling an ancient Babylonian who gave him the tip. Or perhaps the insight occurred after a White House rave party, through the chance amalgamation of some high-quality LSD and ecstacy. The World Socialist Web Site has an excellent article on the Bush administration's response to the report.
I came across a good editorial on this topic.