My point is that teenagers are mentally not adults, and as such, they should not be in the same place as society as adults. I'm not saying they should be completely divorced from it, but I worry when people claim that the concept of a "teenager" is completely a cultural construction. Neurological research indicates it is not.
What would I make different? Not that it's practical (or even non-nebulous), but I would restore the "child-adult continuum" that the article mentions, because I agree with the author when he says the age-based restrictions tend to delay the onset of real, actual, adulthood. Which is bad.
The reason that no one cares too much about an age line like this is that it hits everyone equally and eventually you will age past it. During the years immediately following this event you will see it as as unjust but you demographic insignificance will prevent any real change. Only when you can look back with the benefit of a decade or more of life-experience and hard-won wisdom will you be able to really make an objective judgement; restrictions that were unjust or ill advised from this perspective might change, but I would not expect much to appear unwise...
Logistically speaking, an arbitrary age limit is the best option for the way western urban society is set up (it actually self-reinforces the whole thing). The fact is that society does segregate young from old, and it does delay adulthood for a great number of teens.
But I'm young and inexperienced, and in due time I will see that the way our society is set up is the only way, right?
Yeah, I know it sounds lame, but as a matter of fact you _will_ have a better perspective upon the folly of your youth once you are well past it.
Accumulated experience generally correlates with more appropriate responses, granted. But inappropriate experiences lead to inappropriate responses. How do you verify that your experiences have led to correct conclusions? They are influenced by the society in which you live. And society (the entity itself, not the collection of people involved) generally prefers the status quo, because of natural selection.
Of course there must be a line. There is a minimum level of development necessary for reasonable integration into a society with a specific set of values and expectations. But humans mature at different rates. Age is not the appropriate unit to be using, here. We need a measurement of an individual's ability to _grow_ from immersion in the adult world. Instead of the SATs, we need CATs... Coping Aptitude Tests. It's not such a big leap for the College Board, either. (Now all that's left is to figure out how to measure maturity. Sweet deal.)
Simple, I have experienced life from both perspectives while you have not. You have no basis for evaluating the folly of my adulthood because you have never experienced your own adulthood, while all of us who have made it this far fondly remember the joys and certainties of our youth. I do so miss that period of youthful rebellion, when we managed to figure out a couple of things about life and felt we were ready to pass judgement on everything around us; this conversation is already maxing out my deja vu quota for the week. Enjoy your youth and keep true to what you believe, it is the only way you will ever effect any change in the world, even though the particular cause that started this thread is a fools errand.