In NY and LA they are going to be more lame and you should just be discretionary and smart.
99% chance imo you are fine, but you should probably be prepared with a good exit strategy and not choose a bad spot. Stick to dive bars and such. If you are going to NY cuz you wanna hit the club scene, too bad your not old enough - find some raves to goto and then you can just buy drugs instead. I would steer clear of places with a line to get in.
California is pretty chill, especially about drugs, but on the east coast they will throw you in the slammer for the night and talk to you in the morning. Getting deported would probably suck.
I know u didnt say anything about drugs but you wanna drink underage and while I don't think its that big of a deal, alot of people in this country do. Binge drinking is learned in our high schools and continues past college, its an embarrassing culture we have here that kills alot of young people.
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