Raise minimum age to 21 for everything

Matt Steinglass:

We should raise the minimum age for soldiers on combat duty to 21. Behavioural research since time immemorial shows that teenagers are prone to doing ridiculously ill-advised things, particularly under the influence of peer pressure; mortality actually goes up 200% during adolescence even when we're not shipping the rascals off to Afghanistan; and MRI mapping shows that the brain doesn't finish developing white matter until you're in your 20s.

I agree. If you're too young to buy and use booze and cigarettes until 21, then you're too young for combat duty, driving or voting until 21. It used to be called "coming of age" and has been the tradition for centuries until the commies reduced the voting age to 18.