Sounding old, again…………
Back in the Viet Nam war era…the chant of young men subject to the draft was: “Old enough to die, old enough to vote.
So Congress passed and the states ratified a constitutional amendment lowering the voting age to 18. Then the cry went out: ‘Old enough to die, old enough to vote, old enough to drink’
Many states such as Connecticut lowered the drinking age to 18. NY was already 18.
In a short period of time the number of automobile fatalities caused by teen-aged drunk drivers skyrocketed and there were calls to raise the drinking age. The draft and Viet Nam war had ended.
Only states can set drinking age, no national law would be constitutional, so Congress used the power of the budget. If a state did not raise its legal drinking age to 21, the federal government would withhold Federal highways funds from that state. Thus an almost universal 21 drinking age in the US.