In my opinion no it is not. But, unfortunately from my perspective, there appear to be people that do not agree. And the jails should have room for them all.
Here's my personal feeling about it ... and thank you for using an extreme example as it is often the best way to illuminate a point.
I would personally condemn such a person to death and be willing to pull the switch were I 100% sure they were the perpetrator. Given my lack of certainty I will commute that sentence to life in prison without possibility of release.
But is it evil? I would have to say no. My personal opinion, and again it is only personal opinion, is that some two-legged semi-sentient entities on this planet are damaged goods. Some are damaged by being born with a birth defect and some damaged by virtue of having brains that function in a manner in which they commit acts inconsistent with civility and civilization. We can coexist with and help those with some forms of damage. We are not obligated to help those whose defects are so severe that they hurt others.
Civilization has a right to protect itself from child rapists, bombers, some politicians, and other bad actors. But we should be intellectually honest and acknowledge that this is someone that is (don't care why or how) damaged.
And let me now throw back your way a question equally intended to emphasize the extreme.
My country has a President, and yours a PM, who I believe have done far more damage to far more innocent children than all of the child rapists in your country combined. Why is it that we can all agree that child rape is a crime ... and blowing the arms and legs off a child, killing its parents, and burning its home and family to the ground, a matter where intelligent men might differ and not a single person has been put behind bars? Nor will any be.
So to return to your original question ... I would disagree with your assumption that child rapists, or my President, are of sound mind. Their actions, in and of themselves, indicate otherwise.
