If Muslims don't become FBI informants, they are placed on the no-fly list

"The systematic targeting of travelers for the FBI’s intelligence purposes helps explain widespread reports of Muslim travelers, both immigrants and U.S. citizens, experiencing invasive questioning and searches at airports and border crossings. The FBI has also reportedly threatened individuals with deportation or delayed their visa applications indefinitely as agents try to convince them to cooperate. Others have alleged they were placed on the no-fly list after they refused to talk to the FBI." (thanks Amir)