First off, the word "Immigrant", as it's being used to describe what's
   happening due to NATO's nasty wars is just a cutesy MISUSED term for
   "Displaced War Refugees"
   The "Rioting problem" is the 'ghetto-ization' not the immigrants
   themselves.
   If you were displaced and stuck in a slum after YOUR country was
   destroyed you'd be a little disenfranchised and angry too. Especially
   your children. Even economic immigrant children have issues. And yes...
   That's absolutely an apologia for people displaced by the wars the West
   creates to loot extractive resources.
   But let's talk about "Economic Immigrants" not traumatized by war and
   left without any good psychological care or community support... which
   was left in the airstrike and artillery rubble of their homeland...
   For instance where I live; an area of California with a large
   population of Mexicans. The parents are hard working and for the most
   part fastidiously law-abiding, but the children, if the family isn't
   careful, become gangstas and drug dealers.
   But truth be told, for not-so-different sociological reasons, white
   middle class parents around here are, for the most part, hard working
   ... but the NA and AA halls are full of their kids, who also 'pack up'
   occasionally to terrorize the local displaced workers. AKA the
   "Homeless".
   Something Chicano kids, in my 40 years here have NEVER done.
   From the Washington Post...
   "In 2015, when the influx of refugees and migrants to Europe from
   Africa, the Middle East and Asia was highest, Sweden took in the
   greatest number per capita. By and large, integration has been a
   success story there, save for incidents such as Monday night's, which
   have taken place in highly segregated neighborhoods.
   The newspaper Dagens Nyheter analyzed crime statistics between October
   2015 and January 2016 and came to the conclusion that refugees were
   responsible for only 1 percent of all incidents. That has done little
   to assuage the perceptions, even among Swedes, that foreigners are
   culpable for the crime that does happen. A Pew Research Center study
   conducted in early 2016 indicated that 46 percent of Swedes believed
   that “refugees in our country are more to blame for crime than other
   groups.”
   [1]https://www.washingtonpost.com/news/worldviews/wp/2017/02/21/riots-e
   rupt-in-swedens-capital-just-days-after-trump-comments/
   Ripe ground for Fascism. As with Norway where there's been a hard swing
   to the right as their petro-based economy flounders, it's been seen
   that Socialism of the Nationalist variety... The kind that stops at
   your national borders, easily becomes National Socialism when times get
   economically or socially stressful.
   And so it is in 'Merica too. Which despite it's crapitialist
   underpinnings has required a so-called Welfare State (Nationalist
   Socialism) to remain... for some part of the population... mostly the
   white part... stable.
   Rr

References

   1. https://www.washingtonpost.com/news/worldviews/wp/2017/02/21/riots-erupt-in-swedens-capital-just-days-after-trump-comments/