The 1st Amendment to our Constitution is very clear, that "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof," which would strongly imply that Americans are entitled to worship in any way that they so choose. The only possible limitation on this worship would be meetings held in a house of worship in which the congregants are actually contemplating or planning treason by participating or by actively giving, aiding, or abetting our avowed enemies of the State, to which some of those enemies would include known terrorist groups such as Al-Qaeda and ISIS. In fairness, America has an absolute obligation to protect its people and its borders against foreign as well as domestic enemies to which it is certainly conceivable that some of these enemies would meet in a mosque, as a significant amount of peoples that oppose America and its policies are avowed Muslims.
Where the ground becomes quite shaky though, is that despite the protests of the Executive office or the Department of Justice, that America does not or will not infiltrate and spy upon Mosques without a valid warrant or similar, all that really means in the doublespeak of American government, is that no directly paid FBI agents, or no directly paid NSA agents, will infiltrate mosques, and nothing more than that.
This government has proved again and again, that laws aren't so much meant to be broken or pushed aside as they see fit, but that position papers can be created for virtually any law, with interpretations spun on a given law, allowing the law to be bent, formed, and manipulated so that the government can do what it wants to do, and having created the Orwellian named Homeland Security in 2002, the government and all of its affiliated and subservient departments will not allow, and will never permit, mosques, or other congregations of Muslims to be unmonitored in this world of heightened domestic concern.
This means and signifies for an absolute certainty that at a minimum every single mosque, without exception in America, is monitored, to which the government records the license plates and thereby the identities of the worshippers, the hierarchy of the given mosque, the banking and spending of money at that mosque, the sermons in the mosque, and any other pertinent information that can be observed, noted, or recorded. While this information can be gathered through all sorts of law enforcement or governmental agencies, one of the easiest ways to gather such intelligence, is to have within a mosque, a person or persons that have previously been either compromised by the government, or in need of aid, such as monetary aid, or employment aid, which necessitates their availing themselves of help from the government in return for these people providing the intelligence or information desired by said government.
There is zero chance that today's government is forgetting any of their plays from the playbook of the radical 1960s, instead, it can be stated as an incontrovertible conviction that technology, an unlimited budget, and the general greed of a generation that believes it is forever entitled, makes the governmental work of surveillance much easier thanfifty-odd years ago. To be a practicing Muslim in America is to be monitored, classified, processed, and watched. For those that believe that this is right and prudent, remember that sanctuary wrongly denied for others, will one day be denied for you.