If somebody aggresses, makes terroristic threats, aids and abets evildoers or personally plans or commits a criminal act, prosecute and punish to the fullest extent of the law. Throw the book at them.
But... if a person does none of the above and is, in practice, blameless, leave them alone.
Nobody needs to be sterilized on your say-so. Sterilization is not an antidote to evil. Especially when forced of a person without consent, it is an evil in itself.
The source of evil begins with those that bear them.