Maturity

Citing Harlan Miller's article once again, I found the paragraph regarding maturity particularly interesting.  The varying degrees of maturity are for the most part culturally, politically, and socially determined.  I think that we need to be personally aware of our capacities and developmental stability.  The government dictating that at 16 one is legally free to copulate and operate a motor vehicle is absurd.  Furthermore, the legal separation from ones parents at age 18 creates serious financial, emotional, and personal damage.  I will not evaluate the legal age at which one can purchase alcohol, as it is a moot argument founded primarily in fierce subjective opinion (none of which affects me).
  I will personally say that I did not experience a cataclysmic development until I was about 21 years old. I should have not been legally able to drive at 16, or at age 18 had financial responsibility impressed upon me.  Every situation varies; and I understand my opinions may face great opposition.  However, since my "coming of age"  in which my perspective was drastically altered (an event I was aware of but did not consciously incite) I experience, interpret, analyze, understand, and observe life and all aspects of every imaginable facet differently. 
I understand how different mental capacities are exceptions in these cases, and I respect them but this argument is for general concepts and the interrelation between politics and society- considering safety, emotional and physical stability, and financial outlook.