One of the ways that the government tried to discourage this was by offering increased highway incentives for any states who maintained a minimum. The states were only too quick to volunteer to raise their minimums. The government also threatened to reduce the amount of federal money offered to the states for improvement of the highways. Obviously the states didn't want to lose any money so they complied with the government.
Many people believe that there are other ways to decrease the number of accidents and teenage deaths associated with teenage drinking. Many states have "Zero Tolerance Laws" which severely punish underage teens who are driving with any blood alcohol in their bodies at all. The punishment is usually the loss of the offending teens license, and those officials who stand on the side of lowering the drinking age feel that this would be enough of a deterrent to keep underage teens from drinking and driving. The current standard MLDA is 21, many feel this is unfair because it crosses to many age and social barriers. For instance, many college juniors and seniors can drink, but sophomores and freshman cannot. This automatically breeds unlawful activity, because college freshman and sophomores can't party with some of their friends according to the law. By the time most high school seniors graduate they have already turned 18, and those who haven't soon will. If the minimum drinking age were lowered to 18 or 19 it would dramatically cut down on the number of incidents of illegal drinking on college campuses.
A minimum drinking age of ten obviously makes no sense because no one would expect a 10-year-old to be able to distinguish between an alcoholic beverage and a non-alcoholic one. However, nineteen as a minimum drinking age is a much more realistic goal. The theory is that by nineteen most people have completed or are at least out of high school and are out functioning in a world much older than that of their days in school.