My own experience in was that binge drinking in the university is at least in part a consequence of the inability to drink publicly, in a normal healthy way. A person of 19 or 20 who wants to drink is going to drink, but has to resort to at least semi-clandestine methods to do so - it may depend a bit on how old the person looks; the effects of that are that one gets accustomed to drinking in an environment that does not encourage responsible drinking, but rather the reverse - drink when you can as much as you can. It would be much saner if one could buy a beer in the cafeteria (as one can in any university in Europe) and drink socially. By making illegal a normal behavior, one drives it into anti-sociality.

If you worry about teenage drunk drivers - raise the age for a driver's license.

The basis of the point that binge drinking is encouraged rests upon the point that alcohol is difficult to come across, and this just isn't the case. It's not difficult for 18-20 year olds to pick up a couple of handles of cheap liquor and get drunk off of it. This has nothing to do with "we don't know when we'll be able to do it next" and almost everything to do with "Let's get drunk because it's fun." If the drinking age were 18, the only difference is that the 18-20 year olds would also have the option of binge drinking at bars.

yes but a more important difference is that bars have remarkably more leeway to discourage binge drinking than peers of an average college student do. whether the bartender chooses to exercise the leeway or not is a completely separate issue, and complaints along those lines should be directed at the bartender, not the 18-20 year old.

"If the drinking age were 18, the only difference is that the 18-20 year olds would also have the option of binge drinking at bars."

You forgot to add: "where, of course, they'd at least be monitored by establishments with a vested interest in their safety and that of those around them, given the states' increasingly aggressive use of dram shop liability laws and the financially ruinous (or even criminal) penalties which attend them."

There, it's fixed.

And so then when the bar kicks them out, since the drinking age is now 18, there's no way they're just going to go back to the dorm room and keep drinking.

This doesn't address my original point, that 18-20 year olds don't drink in binges because it's taboo, they drink in binges because they want to be drunk. Lowering the drinking age doesn't make kids automatically less stupid.

They are not Kids! They are adults and should be treated as such, for better or worse.