I'm under the assumption that this is an obsession. And any obesession is dangerous.

If I love your wife and would marry her if she was available, that is not necessarily an obsession.

If I spend every waking moment thinking about how to seduce her away from you, that is an obsession.

Being a pedophile is no more inherently obsessive than being attracted to adults.

I agree, any obsession is dangerous. Some of the seemingly obsessive "I'll kill anyone who lusts after my children" comments make me worry that the posters in question are dangerous.