Why should it be illegal to “pander” virtual child pornography when it is not illegal to possess it?

Millions of pornographic images of children are available on the Internet. Some of these images are of actual children engaged in sexual activity. Others are virtual (computer-generated) pornography— that is, images made to look like children engaged in sexual acts. Whereas child pornography is illegal, the United States Supreme Court has ruled that virtual pornography is legally protected under the First Amendment because it does not involve the exploitation of real children. In its ruling, the Supreme Court struck down as overly broad, and therefore unconstitutional, provisions of the Child Pornography Prevention Act of 1996 (CPPA), which, among other things, prohibited any visual depiction including a “computer-generated image” that ”is, or appears to be, of a minor engaging in sexually explicit conduct.”