changing the drinking age

i think that they should change they drinking age because i think that if you can fight and die for your country you should be able to sit down and drink a beer. they shouldn't really go by your age because in the 60's and 70's the drinking age was 18 why did they change it for its the same thing as buying cigarettes you have to be 18 to buy those and you can still buy them even if you are under 18 same as alcohol some people don't care about what they sell to minors.