What states let 18 year olds and above in bars?

you mean in the USA? I think none of them... but other countries in the world let it. Well, I am from Slovakia(EU - Central Europe) and officially 15y olds and above can be in bars whenever they want (under 15 can be only until 22:00) and consuming alcohol is allowed (officially) above 18... but most of the bars have no problem with selling alcohol to kids under 18, so it is a common thing to see drunk 12y old little girls Friday nights in the towns here :)