In a way very different from how many European nations are threatened by extremists among impoverished Muslim immigrants, the U.S. has enjoyed a harmonious relationship. Muslims, more ethnically diverse than any other significant religion in the country, have fit in. They hold more graduate and postgraduate degrees than the national average, and so also have a lower unemployment rate and more professional jobs.
Over the years, Americans may have thought Islam exotic and odd, but hardly worth getting excited about. For instance, I can remember when the popular singer Cat Stevens gave up his music to become a Muslim. Americans were sad - not about the conversion, but about losing his songs.
Of course, Americans seldom need much of a spark to ignite their racial or religious prejudices. Witness their treatment of Native Americans, hatred of Irish immigrants (and the concurrent anti-Catholicism), the ban on southern (but not northern) European immigration in the early 1920s, the internment of Japanese Americans, the century of overt discrimination against African Americans, and today's freak-out against immigration from south of the border. So it is hardly surprising that simmering anguish over 9-11 didn't need much of a spark, either.
It actually started in small steps, like when the state Legislature of Oklahoma (Muslim population 0.81 percent) passed a law last spring banning judges from using shari'ah law in their decisions. But when a Muslim group, long in the New York neighborhood of the Twin Towers, decided to build a Muslim center devoted to improving relations with other U.S. religions and opposing by their example extremism, it unsurprisingly came under fire by professional and amateur haters, opportunistic politicians, and such demagogues as are to found on Fox News and the like.
Never mind that it is exactly this kind of moderate Islam - and an adherence to our republic's principles - that is our best hope for combating terrorism - especially the home-grown variety.
In the past, American prejudice in this regard really hasn't threatened (other than morally) the country. Or its soldiers. Today, that's not true anymore.