[dzchwgil] Why prevent child molesting

Why is child molesting treated separately from other sex crimes?  Some possibilities:

1. Children cannot vote, so cannot participate in the democratic process to protect themselves.  This logic is a little bit ludicrous: we need laws against child molesting in order to prevent us from passing laws legalizing child molesting.  The logic might make sense in the context of hierarchical jurisdictions with upper laws trumping lower ones.  If the logic is true, immigrants (resident aliens) would be another group requiring special protection.
2. A sex crime can cause a lifetime of trauma.  A child has a longer lifetime ahead of it, so consequently should receive better protection.  Continuing this logic, is the amount of punishment meted out for convictions negatively correlated with the age of adult victims?  Should it be?  Following this logic, sex crimes occurring against students in college should be given more consideration than against nursing home residents.  This vaguely seems to be true.
3. Children are locked into special legitimate power structures: family, education system.  We need special laws to complement these power structures to protect children from those power structures being abused for sex.  In contrast, the power structures that adults participate in are, or are seen as, more fluid.  Those who have power are competing against each other so cannot abuse their power too much (for sex) or else the underling will (and can) leave to another power wielder: marriage, pimp-sex worker, labor market.  Not sure how practically true this is, but it does seem adults have more ability to leave than children.
4. The kind and amount of sex and sexually related activities a child has and does may have a strong influence on their attitudes toward sex, especially attitudes toward promiscuity.  These attitudes, and consequent behavior, are social class markers, so will have very strong effect on the opportunities available to a child (and to the child's descendants).  It is important that power structures be able to control and program a child's attitudes toward sex in order to maintain social class boundaries, and the advantages they provide to some social classes.