<p>I'd venture to say that a significant portion of underage drinking comes from the sheer appeal of a forbidden fruit, breaking the law, and all that good stuff. Even in other countries that do have lower drinking ages, they don't see such egregious binge drinking because alcohol isn't treated as "You touch it, you die." Countries like France and Germany treat wine and beer as part of their cultures, and don't have much of a problem with domestic drinking.</p>
<p>There was an article posted here maybe a year ago about American students who go off to Canada for college. The first semester or so, sure, they're partying and drinking thanks to the lower drinking age. After a while, they settle down and treat alcohol as a special drink, or at least something not primarily used to get tanked.</p>
<p>Drunk driving in the U.S. was a major issue partly because states didn't have the same drinking ages, so of course younger people would drive over to another state and try and drive back while drunk. All states need to be on board with a common age, which in my opinion should be around 18. That's clearly the age of adulthood for most considerations, and the way our society is currently, is the best we can do for a while. Most of underage drinking problems are societal and social issues, which take more than legislation to fix. See banning slavery, Jim Crowe Laws, segregation, etc.</p>