The vast majority of Islamic terrorist activity in the US comes internally. As in they have perm visas or citizenship here. Heck a large number of ISIS fighters overseas are European and US citizens.
But there is a difference between a visa stay/snuck across the border and natural born when it comes to stats. Same thing when it comes to race and all that stuff.
The numbers are alarming. The Metropolitan Police Commissioner in London recently said that five British citizens are joining ISIS every week, swelling the ranks of European Muslims believed to number in the thousands.
One is a 21-year-old California man accused of trying to travel to Syria to join ISIS. The other a 17-year-old Virginia student charged with recruiting.
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