This confirms what I've read elsewhere: Colin Powell pushed the public discourse toward the WMD against the objections of others; he was told that he had to make the presentation to the UN because he had made the WMD into his issue, and now that the media have concluded that WMD have not been found, he is disassociating himself from this intelligence, arguing that he was misled by some engineer.
Sure, mistakes were made, but they seem to have come from State.
After all, how could Powell have advocated the terrorism argument, after stating that "one man's terrorist is another man's freedom fighter"?