If you read the TERMS AND CONDITIONS it says it in there....usually towards the end...its good to read that anyways.....BUT now i really read it over...
And actually today i reaserched what would happen to me , if i did buy into an ICO that said NOT OPEN TO US CITIZENS" and people have done it, and nothing happens to them! Some people were able to buy in....and trade their tokens, or sell them...some one wrote, bexause it is decentralized there is no way to regulate it (yet) but its digital currency, not a currency of a specific country...so technically its not illegal, and the people who write up the contrats put the NON US CITIZEN lingo in there incase something were to happen the company of the ICO can not be held liable for US regulations,...its pretty smart...so i guess u can try to buy in even if it says NON US CITIZENS, at your own risk..i am going to try it just to see( with a very small amount of money) you should look it up too to see what others US CITIZENS have done and said, when buying into an ICO that is not for US CITIZENS. Ill let you know how it goes when i do it...best of luck.