Maybe we should take a clue from Japan, at least when it comes to Muslim immigration, particularly radical Muslims.
“Islamic Terrorism: Why There Is None in Japan
“With all this Muslim terrorism plaguing the world, perhaps it is time to take a look at a country not suffering the same fate and analyze exactly why that is…(SNIP)
What Japan did to avoid problems related to Muslims was much simpler and cheaper; Japan is practically closed to Muslims.
Officially, immigration to Japan is not closed to Muslims. But the number of the immigration permits given to the applicants from Islamic countries is very low. (SNIP)
Japan officially forbids exhorting people to adopt the religion of Islam (Dawah), and any Muslim who actively encourages conversion to Islam is seen as proselytizing to a foreign and undesirable culture. Too active “promoters of Islam†face deportation- and sometimes even a jail sentence.
excerpt: http://chersonandmolschky.com/2015/04/13/islamic-terrorism-japan/
The majority of muslims in America are first generation immigrants.