Most of our immigration is coming from Latin America, which is historically Catholic, with a sizable evangelical minority, or from East and South Asia (some Muslims from Pakistan or Bangladesh, but mostly a mixture of Buddhists, Hindus, Christians, and nonbelievers). Unlike the case in Western Europe, Muslims are a decidedly small minority of America's immigrants.
We may have serious problems, but the possibility of radical Islam coming to power is not one of them.
Are you willing to bet your children and your country on that? If so, it logically follows that you believe we have no business trying to stop the spread of militant islam.
If you seriously believe you do not have to be worried about Islam affecting your society then you need to think again.
IMHO there are areas of the US that are as badly affected as any in Britain or Europe