>If the "illegal" pornography involves individuals who are capable of making a conscious choice about the acts they engage in, then yes, it should be legal. If the "illegal" pornography involves coercion and/or rape of anyone, or animal, involved, then no, it should remain illegal.
Ignoring for the moment that I can kill and eat an animal for my own pleasure... we aren't focusing on if it should be prohibited, but if prohibition of it would work.
People will say that prohibition of drugs is stupid because prohibition fails. I'm interested in if this argument, not the argument that drugs shouldn't be prohibited for any other reasons, holds up.
Illegal porn, at least of the digital variety, is easier to produce and trivial to copy compared to drugs. If prohibition of drugs is doomed to failure irrelevant of one's stance on their morality, then should not the same be true of illegal porn?
As for what I mean by illegal porn, pick whatever you think should be made illegal for whatever moral reasons you want. If you want to ban midgets because Shiva told you so; it doesn't much matter why because my point is talking about the argument that prohibition inherently fails regardless of the moral judgments upon what is being prohibited.