Twitter is in the spotlight because of its new and controversial per-country blocking system--the power for governments to censor and withhold public tweets that violate local laws. Although the specifics are a bit murky, according to Foreign Policy magazine, here are 5 things that you can't/shouldn't do on Twitter in the United States, for they can lead to some serious legal trouble: Cyberbullying, pranking police, coordinating unlawful behavior, threatening violence and not removing tweets by request. Check out the full implications of each here and stay out of Twitter trouble!