Seriously, what's the argument for porn being speech and expression? What is the message it's trying to convey?

Edit: Guys, I'm asking if it's speech/expression and, if so, how. Most of the comments in support of it aren't answering the question, just showing their support for free speech and expression, in general. Only one guy has made a case for it, comparing it to car shows and art. And, even though I have reservations about labeling it as art, I appreciate that he's making a case for it and not just side-stepping the issue.