The alternative I suggest to a radical youth liberation argument is not youth enslavement or unlimited state power.

Just to make things clear, I am not suggesting a "radical" youth liberation, but simply one that was more or less complete. "Radical" would entail things such as actually giving youths rights and privileges that adults do not have (something many who oppose youth lib seem to fear), which is certainly not what I'm suggesting. It would also not entail endorsing irresponsible policies like giving young children who are not physically or cognitively capable of driving a car the right to do so without having to pass a competency test when not even adults are allowed to do this. As I noted with the examples of reasonable rules and regulations for younger children in a previous discussion thread with you, I take a reasonable though complete stance on youth liberation.

It is one where liberty is the assumption (especially in cases where parents and children agree), and we carve out specific exceptions to reflect our most basic moral values as a society.

I will not disagree, but with the following point made clear: It depends on what you mean by "moral values." As often noted in progressive circles, there is a difference between morality and moralism. The former is concerned with objective and demonstrable considerations, whereas the former is more concerned with decorum and interpretations of "tradition." As examples: Rules that do not permit someone to hit another person or threaten them with assault outside of self-defense is based purely on harm-avoiding ethics. Rules that prohibit a certain type of harmless sexual practice behind closed doors (e.g., "doggie style") simply because many people find it revolting to their personal sensibilities and "degrading" even to females that clearly glean pleasure from it is based on pure decorum. The former should be enforced by laws and regulations; the latter should not.

Something like a girl choosing genital mutilation isn't an extreme example -- it could be the basis for a law specifically prohibiting people from performing such surgeries on minors.

That would only be justified in a youth liberated society under two conditions: 1) That choice was also legally denied to adult women; 2) If those who were designated minors would be legally denied access to objective information on the subject and/or to receive professional objective medical advice on the matter so they would be unable to learn enough to make an informed decision about it - which is dirty pool.

The question of whether anyone should be allowed "self-mutilating" surgeries in a democratic society is an entirely different topic.

Each of these cases I mention can be addressed separately. But all it takes is a person's clear conviction that ONE of them is a valid cause for state intervention to undermine radical youth liberation.

Only if the majority of people continue to buy into extreme examples like this, and to realize that it makes no logical sense to deny freedom of choice because someone might make an extreme decision that society at large would find unsettling, or that something bad might happen despite not being very likely. Note how our society prioritizes its concerns based not on scientifically proven likelihood for lasting demonstrable harm or death, but based on those that pull our emotional and moral heartstrings the most.

For example, statistics make it clear that a child is much more likely to be harmed by being struck by an automobile, drowning in a swimming pool, or struck by a bolt of lightening - lightening actually kills or inflicts debilitating effects on more people in the U.S. per year than tornadoes or hurricanes - than making decisions to engage in sexual activity. In fact, far more people are harmed by lightening per year than kids having harm inflicted upon them via "stranger danger," our culture's greatest bogeyman. Yet our society fears the media construct of the "pedophile" far more than it does the "lightening man."

Further, cars, swimming pools, or being out and about during a thunderstorm are not prohibited for the protection of kids, nor is nearly as much concern put into these dangers than the concern over the far less likely possibility of "long-term" harm resulting from mutually consensual sexual activity. This is because of two reasons: 1) The first three things are acknowledged to be preventable if certain sensible precautions are taken, which can easily be taught via education and open access to information (note the many precautions listed on the linked site about the dangers of lightening); and, 2) Because the greatest true dangers to kids do not pack the sheer emotional "punch" or affect our society's "moral" framework nearly as much.

In other words, we find the thought of kids being sexual - particularly though not exclusively with an adult, as the recent draconian attacks on peer-to-peer sexting have proven - far more unsettling and disgusting than we do the thought of them being struck and crippled/killed by a car or a bolt of lightening, or of drowning in a pool. Hence, we find no need to circumvent democracy with unreasonable, draconian rules regarding the three real, demonstrable dangers I used as examples. The consequence of putting far more concern into protecting kids' moral reputations and adherence to our societal conception of "innocence" is far less taxpayer money invested into safer community and pool design that would prevent many avoidable deaths and severe injuries than that which is invested into numerous expensive and invasive surveillance projects designed to detect, counter, and punish instances of youths engaged in sexual expression; or to hunt down adults interested in viewing such expressions.

This is the equivalent to the manner in which so many adult voters put considerably more concern into emotionally charged and moralistic "wedge" issues than into issues that actually impact upon our lives in a major way during elections, e.g., considering how an incumbent feels about homosexual marriage to be far more important than his/her stance on economic policy that our jobs and social programs which help us support ourselves and our families' material necessities and comforts.

From my perspective, the question most directly relevant to this group is whether prohibiting adult-child sexual activity is one of those cases. My position is "yes", though with qualifications and without the venom society brings to the issue. There are subtle points to be discussed.

I think it's of central importance to those truly concerned about child safety, as opposed to established cultural norms, to consider that the major causes of scientifically demonstrable forms of long-term harm that affect millions of kids across the world are neglected in favor of those which we find the most unsettling from a moralistic standpoint. Those who do that are basically moral crusaders, not advocates for a truly safer world. You don't need to circumvent freedom of choice in most cases to achieve a better and more democratic world.

In contrast, winning hearts and minds against radical youth liberation is easy with an appeal to moral intuitions (not emotions).

Moral intuitions are bolstered very heavily by emotions, otherwise they wouldn't have the degree of venom, lack of reason, and disproportionate levels of concern over and above far more demonstrably important issues, let alone our cherished concepts of freedom, injected into them. You cannot divorce moralism from emotion, because the latter is the fuel of the former. Logic and reason are the fuel behind genuinely practical concerns, and they lack the sheer force of emotions. I explained above why the greatest and most demonstrable threats to the safety of children and adolescents are gleefully neglected in comparison to those that simply violate deeply beloved customs.