I think its pretty solid that pedophilia is not going to be going away any time soon.
I also think that, however disgusting it is, my foremost concern is about the children that are sexually abused or exploited--that's the harm, and that's ultimately what is intolerable.
The effect of a lot of current legislation is essentially to NIMBY Pedos to rural / exurb locations, which might work locally but collectively just means that they'll grab different children instead.
Can we just ship the Pedos away?
We could. By a twist of fate, there is at least one exotic location where this behavior is somewhat normal:
Pitcairn Its like FATAL decided to stop being the worst RPG ever and decided to become a real place--but among its problems is a culture of exploiting children. There is a logic to ensuring that it's not your own kids that are victims, but that's about where we are now.
Can we kill them all?
Maybe. Ultimately, I think it will be very possible to determine whether a fetus would ultimately become disposed towards being a Pedophile. I'm not sure what to look for there, but if that were cracked open it might be normal simply to screen for it as much as screening for genetic defects. This could have really wild effects--like causing large numbers of brilliant supermodels to be born--but this definitely a good reason to start with.
We really can't give them .357 neural injections without undermining freedoms as defined at law. Due Process is a lynchpin of our legal protections, so that's out of the question--we'd ruin a lot of other things at the same time. There's no magic legislation that can say "Kill all the Pedos" without implicitly supporting laws that say "Kill all the X" might also be legal.
My gut take on it is that we need to separate "Real" from "Virtual" when it comes to Child Sex. They're both horrible and I never want anything to do with them, but the real harm is abusing children. I'm aware that various studies have shown that access to mainstream porn reduces sexual crimes; I suspect that CP probably serves a similar role.
I think legal policies are starting to head in this way, where virtually generated CP isn't necessarily being treated the same way--and I think that until we can stamp out Pedophilia via genetic enhancement, it may more sense simply to allow a legal "Virtual" means to keep pedos away from real children. It seems like the best of a bad set of answers, though.