Subject is being changed, however raising the age to 21 will create a shortage and 18 year olds are able bodied (Draft is designed to protect your homeland, 18 is old enough to fight). States should determine their own drinking/smoking age.
The problem is what defines the age of majority, and if that should be uniform across all states, as well as the Feds.
If one has reached the age of majority, then they should have complete rights that are not age-restricted.
The biggest indicator that one has reached the age of majority is the ability to vote and the requirement to sign up for the draft. Whatever age this is, no other age limits should be put on these citizens.
If that means making the voting and draft age 21, so be it. But I thought it was stupid that at 18, I could be drafted but not have a draft beer, and that I could be trusted to shoot a rifle, but not a shot of whiskey.
Just my opinion. YMMV. Peace.