Really, where's it going? I read the text of the law and it seems pretty clear to me. I don't have a problem with outlawing this material at all.
But what's wrong with drawings that makes them more than simply free speech?
http://www.usdoj.gov/criminal/optf/links/citizens_guide.html
I'm not saying this a good law, but anyone who has this kind of stuff should know that the "it's just ink on paper" argument cuts no ice with the judges.