I am not saying those regions only have bad people. Lots of good people, just some bad apples.
But in USA you usually get whole families and not a bunch of young single men. That's one factor that de-risks the integration. The second factor is you get people that can afford plane ticket (likely more educated) and go through some form of border check.
I believe the vast majority of the Middle Eastern people in California are Persians. Again, that's a nationality that fares well in inclusion even in Europe.
I am all for immigration, we need it, we are an aging continent. But we should be a little bit more picky and cautious. And I am not saying we should not get any people from Afghanistan, Iraq, Syria or Horn of Africa, it's just often people coming from these countries have a risky mix of low education and culture that doesn't respect women or institutions.
And it's not islamophobia from me, that's why I specifically say culture, not religion. Persians are often muslims and fine, same for Indonesians or Turks.
Problem is we can't have meaningful and polite debate about it like I have with you - you get immediately labeled as racist or xenophobe. Thus the sad rise of far right groups in Europe.
On this note, I am sad that someone is downvoting/flagging you.