Agreed. Why should we allow in even one immigrant from a Muslim country? That's not to say that there aren't talented, reasonable, and peaceful people living in those countries that would make good immigrants, but rather why should we even take the chance? By barring people from Muslim countries, are we going to sacrifice anything? Not really. We'll get by just fine.
Having a large congregated immigrant community -- even if peaceful and industrious -- still allows for a sanctuary and refuge for those that aren't so peaceful and industrious. Muslim immigration -- not worth the risk.