Michael Yon: "Pornography and propaganda are closely related, as they are both cynical attempts at manipulation, rooted in a lack of respect for humanity."

Even though that's not what his article is about, to me it represents a pretty accurate and concise definition of what separates erotica from pornography. Well, it does in my opinion at any rate. Deciding what represents "respect for humanity," and when that line is crossed, is unfortunately rather open to interpretation. Were it otherwise, I think the whole adult industry would most likely have a much easier time doing business.