Well- of course- the MAKING of hard-core child porn is harmful to the child, and is a heinous crime.
But then after that you get into waters where things aren't as clear. If the "kiddie porn" only involves nudity- no actual sex- it that harmful to the child? Some would say it's just our Victorian prudishness that says "the naked body is an obcene thing", an dthat "nudity is a natural and good thing".
I know one can argue that buying kiddy porn aids ands abets the person who makes it, who possibly wouldn't make it except for the chance someone would buy it. But since there were penty of sites where perverts would download for free their "work", it seems like a lot of the current kiddie porn swirling around out there isn't commercial in it's original purpose. Then again- if one doesn't buy it, but just looks at it- it's going to be hard to say that that hurts the child who was the victim.
It has been hotly debated- even here- whther or not simple "possession" of "kiddy" porn should be such a serious crime.
Note- I am not advocating "free kiddie porn"- I am just playing the "Devils Advocate" and pointing out that not all agree that "child pornography is a bad thing". It's a complex moral subject, not a simplistic one.