Muslims can be allowed to impose Sharia law anywhere they want in America. Why? Because it is religion, and they have freedom of religion in America, just like everyone else.
The catch for Muslims is what will happen to them if they apply certain aspects of Sharia law in America.
American law trumps Sharia law. If a Muslim in America harms another person or his property, just like anyone else, he can be taken to court, and if found guilty, punished for his actions. This includes if a Muslim actually threatens someone else with a real threat.
The really difficult question has to do with how much Muslims will take. When they find that American law is much more favorable to them than Sharia law, how long will it take them to convert away from Sharia? Or if they won't convert, how much punishment will it take via the American court system until they move out of America?
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)