The most certain test by which we judge whether a country is really free is the amount of security enjoyed by minorities. Originally said by Lord Acton. (He was christian, by the way) Sources for the quote are here and here.
Now, some people are advocating treating muslims as second class citizens. Some suggest that muslims and only muslims should be subject to very invasive "security checks" at airports. Some are opposed to allowing them to build any structure which might get used in part as a mosque too close to ground zero (i.e. anywhere in the country.) I've heard the excuses. They are, no doubt, very persuasive to those who want to treat muslims like second class citizens.
But, if we allow oppression, anyone could be next. And that is what that is about. Muslims make for a good target for oppression in this country because there are few of them here and because it is easy to find nutcase leaders abroad. But, right now, I think it is time to speak up.