The only reason it's not 18 is that politicians haven't had the balls to stand up to groups like Mother's Against Drunk Driving and say: "Yes, what happened to your child was tragic, but having the drinking age be 21 is not an appropriate reponse. An 18 year old can kill someone if they drink and drive, but so can a 21 year old or an 81 year old. And someone killed by the latter two is just as dead as someone killed by the first."
There’s also the fact that MADD existed in a less politically polarized era. I suspect that if MADD was starting out today, politocal polarization would stand in their way.
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