Can people who are residents of United States apply for the ICO?
According to their FAQ:
No, residents of the United States can't participate in the SONM tokens distribution because of the US laws.
You can participate in the SONM ICO if you are neither a U.S. citizen or permanent resident of the United States, nor have a primary residence or domicile in the United States, including Puerto Rico, the U.S. Virgin Islands, and any other territories of the United States.
Sending from an ether wallet and receiving tokens seems like anyone could theoretically participate without anyone knowing anything about who actually participated...