Well ICO regulations are coming to the US more soon than later
You can't really regulate ICOs. A few people will be put off, but more than enough US citizens simply won't give a damn and invest anyways. Regulation never stopped the flow of money and it never will.
Countries that will give most freedom will gain most on long term. Companies will just avoid countries like USA. That will be huge loss fro them. For country are not that impotent investors that companies itself. They pay taxes. And if those companies will not be welcomed in USA will pay taxes elsewhere. It is simple. Countries that realized this already will gain most.