Freedom of speech is worthless if it's restricted to things that'll never offend anybody.
Freedom of choice also requires that we be able to choose things other people think are dumb. Otherwise, what's the point? You might as well flip to a world where you're given a menu of permitted choices and where you're forced to pick one of them instead of carving out your own path.
Here's Will Wilkinson at The Economist on Cassandra C's forced chemotherapy. She's 17 and refused chemotherapy, with her mother's support. She is likely to die as consequence.
It's simply maddening. Let's recap. Cassandra's mother does not force her to submit to an unwanted treatment, so she is an unfit mother. Cassandra is therefore held hostage by the state and allowed to return home only if she pays a ransom: submission to the unwanted treatment. Held against her will, and very afraid, so she agrees under duress. But she hasn't really changed her mind about the treatment, so she reneges. This is then used as evidence that she was insufficiently mature to be allowed to make her own decisions about the treatment in the first place. Dizzy yet? It seems that the only thing that would have counted as dispositive evidence of Cassandra's maturity, of her capacity to withhold consent, was a willingness to grant it.
I suspect Cassandra has some dotty ideas about chemotherapy. Perhaps she inherited them from her mom. It may be that if she were allowed to act on her dotty ideas, she would die, while chemotherapy may save her (Hodgkin Lymphoma is one of the more treatable cancers). But liberty is a completely empty ideal if we are free to act only when our conception of our interests coincides with those of experts, medical and otherwise. If we are entitled to choose on our own behalf—or on our children's behalf—only when we are deemed rational, and rationality is defined to mean a consensus with the authorities, then autonomy is a bad joke. Cassandra's case illustrates the technocratic tendency of American culture and politics to nibble away at the edges of our autonomy, to deprive us of the right to make anything but the medically correct choice.Emphasis added.
Every time I make this point on rationality, the public health brigade here insists that I'm arguing in favour of some blackboard model of perfect rationality. Rather, deviation from what public health doctors think is best, where those doctors don't seem to give a whit about the patient's experience other than QALYs, sure ain't evidence of irrationality.