Most immigration to the US consists of Hispanics who are relatively mild, only committing about 2x the crimes of the rest of population. I was referring to countries like Sweden which are hell-bent on importing Muslims and Somalians and the like.
As to social strife, this is a standard book, even though written by a leftist, who tries to make the best of it.
The reality is more simple:
"Immigrants were five times more likely to commit sex crimes"
I absolutely do not believe that number. It is almost certainly more like 10 or 15 times. The Swedish government is a pure head-in-ass creature, and almost certainly bending the statistics.