lower the drinking age from 21 to 18

The drinking age in the U.S. is 21, yet people can be drafted/join the military and die for their country at 18. If the drinking age is lowered it will eliminate alot of underage drinking charges lowering crime rates. It would also save tax payers money because of the cost of processing people after being arrested for underage drinking and contributing to minors and save space in courts and jails for more severe offenses. The money saved could be used to house and prosecute more dangerous and violent offenders