You sir are either a fukking idiot or are trollin something vicious. If you're as intelligent as you believe you are then you know that taking arguments to the extreme to try and prove a point only makes your argument seem baseless.
I really don't want to entertain this, but I'll do it anyway. The obvious and I mean GLARING difference in my argument and yours is that at the age of 18 you achieve adult independence. You can do things like, you know, go die for your country. But God forbid you want to play pro sports, GTFOH!
Did you just really compare an 18 yr old to a 14 yr old? You are out of your fukking mind!
Make it 16. Or 18 in some places. The point is the same. It's a privilege to play in the NFL. Your argument is based purely on anecdotal evidence.
This whole "kids can join the military" argument is bullshyt too. 18-19 year olds can join the Army because the demand is there. The demand for 19 year olds playing the NFL is next to nil.