That is the argument, wasn’t is, that the assimilationists always gave, that everything would come out in the wash, or in the salad mix, or whatever cute metaphor was employed:
  https://www.amren.com/news/2019/09/report-migrants-children-are-more-likely-to-commit-crimes-than-parents/
  https://voiceofeurope.com/2019/09/report-migrants-children-are-more-likely-to-commit-crimes-than-parents/

“A recent study conducted by Statistic Norway has revealed that the children of immigrants commit more crimes than their parents – first-generation immigrants – do, suggesting that the notion of integration is merely a fantasy. Figures from the study showed that Norwegian-born men with Somali family background in the age group 15 to 35 were 4.6 times more likely to have committed a violent crime. Furthermore, men in the same age group with Iraqi backgrounds were 4 times more likely to have committed a violent crime. And again, the same pattern can be seen in Moroccan Norwegians (3.2), Turkish Norwegians (2.8), and Pakistani Norwegians (2.4). For members in Norway’s rightist Progress Party, these figures clearly indicate that proper integration is not taking place and that the Norwegian government should take more action and “make more demands” to address the problem.  Sigmund Book Mohn of Statistics Norway told the Swedish newspaper Aftenposten, “There are significantly higher rates among immigrants for certain types of offenses, such as mistreatment in close relationships. And significantly lower for other types, such as embezzlement.” Jon Helgheim, the Progress Party’s integration spokesman said that this essentially means that “integration doesn’t happen automatically over time”. “From 2015-2017, a total of 443 people were charged with “mistreatment in close relationships”, including domestic violence. Of those 443 individuals charged, 185 of them were immigrants. This clearly points to significant over-representation.

Directly referencing the problem, deputy leader and former Integration Minister Sylvi Listhaug said, “We have to stop hushing it down.” “It is not so that showering them with money and services, which Norway has been good at, solves the problem. We must make more demands and check better whether the integration measures have any effect,” Helgheim and Listhuag said. A 2017 report from Statistics Norway also revealed that migrants from certain countries were over-represented in crime statistics. In the report, migrants from Somalia, Iraq, Iran, and Kosovo were all substantially over-represented in crime per capita data during the period between 2010 and 2013. The report also revealed that second-generation migrants were, in fact, typically more likely to commit crimes than their parents. However, refugees’ children were the exception. In recent years, the percentage of Norwegians with immigrant backgrounds has sharply risen. Today, close to 17 percent of Norwegians have roots abroad.”

     While being not yet at the Sweden level, Scandinavian countries like Denmark, have their own crime crisis:
  https://www.gatestoneinstitute.org/14839/denmark-crime-sweden

“Sweden is exporting not only its bombings to Denmark. Gang crime, with its shootings and murders, has also traveled across the border. Denmark has experienced 10 bombings since February. The latest took place on August 27 in a residential complex, Gersager, in the Greve area, very close to Copenhagen. No one was injured, but the building was seriously damaged. This year, the Swedish city of Malmö has experienced 19 bombings. An August 16 editorial in the Danish newspaper Berlingske Tidende said: "No one wants Swedish conditions where shootings and bombings have reached an extreme degree. In addition to conflicts in the gang environment, there have been bombing attacks against police stations as well as courthouses, a town hall and the Swedish Tax Agency in Malmö in recent years." The piece was published after the Danish Tax Authority in Copenhagen was bombed on August 6, destroying its façade; one person was injured. Two Swedish citizens were charged with the attack. "The Swedish suspects have names that indicate that they have a different ethnic background than Swedish, but there is as yet no knowledge of the motives that may have driven them," Berlingske wrote. A few days later, on August 10, Copenhagen experienced another bombing that caused material damage, this time against a police station in Nørrebro. Shortly after the bombings of the Danish Tax Authority and the Copenhagen police station, Danish Prime Minister Mette Frederiksen held a press conference. The government, she said, views the bombings "as an attack on our authorities and thus also our society". She added that the government plans to strengthen the border with Sweden. "We have a challenge. It should not be the case that you can travel from Sweden to Denmark and place dynamite in the middle of Copenhagen". She stressed that the border "has our full attention. And it needs to be strengthened".

While the motives behind the Danish bombings are apparently unclear, Swedish journalist, Joakim Palmkvist, who has been following crime developments in Sweden, told TV2 Nyheder that there are certain similarities between the bombings in Denmark and Sweden: Whereas the bombing targets in Sweden have often been residential complexes, businesses or restaurants, the police have also been targeted several times. Most recently a town hall was targeted in Landskrona and hit by a large explosion. According to Palmkvist, Swedish police believe that these bombings are due to mainly two motives: Blackmail, when criminals want money or services from their victims; or as revenge against the police for moving against the criminals. Sweden is exporting not only its bombings to Denmark. Gang crime, with its shootings and murders, has also traveled across the border. In July, three Swedes were arrested in Stockholm on suspicion of a double homicide of two Swedish men in the Danish city of Herlev on June 25: a Swedish gang leader and another man had been shot dead. The two men were reportedly killed in Denmark as part of a conflict between the Swedish gangs "Dödspatrullen" ("the death patrol") and 'Shottaz'. Although the dramatic escalation has been imported from Sweden, Denmark is experiencing its own problems with crime, especially that committed by male migrants. As reported by Berlingske Tidende in April: "The figures [from the report for 2018 from Statistics Denmark, the national statistics agency, 'Immigrants in Denmark in 2018'] show that crime in 2017 was 60% higher among male immigrants and 234% higher in male non-Western descendants than the entire male population. If one takes into account, for example, that many of the descendants are young, and Statistics Denmark does so in the report, the figures are 44% for immigrants and 145%for descendants, respectively. If further corrected, for both age and income, of immigrants and descendants from non-western countries, the figures are 21% and 108%".

As for the nationality of the criminal migrants, Berlingske Tidende reported: "At the top of the list are male Lebanese who, as far as [their] descendants are concerned, are almost four times as criminal as average men, when [the figures are] adjusted for age. [That is] sharply followed by male descendants from Somalia, Morocco and Syria. The violence index is 351 for descendants from non-western countries. They are 3.5 times more violent than the population as a whole. Descendants from Lebanon have an index of violent crimes of 668 when corrected for age." On August 25, a 31-year-old woman, Karolina Hakim, was shot to death in broad daylight in Ribersborg, a peaceful, relatively affluent area of Malmö. The murder sent shock waves through Sweden, not least because the woman was holding her newborn baby in her arms. The man who was accompanying the woman, reportedly the father of her child, is mentioned in Swedish media as having been part of a spectacular robbery in Denmark in 2008, for which he was sentenced to eight years in prison. Only two days later, an 18-year-old woman was shot to death in an apartment in Stockholm. Denmark is still relatively far from having reached the kind of crime epidemic that is currently plaguing Sweden. However, given the proximity of the two countries, the open borders and the apparent free flow of criminals across the borders -- not to mention Denmark's own crime level -- there seems little to stop the situation in Denmark from getting out of control and becoming increasingly more like Sweden.”

     Thus, the Swedish disease is more like a pandemic which will continue to roll over Western Europe until every city becomes a post-apocalyptic version of Malmö, rivals to Baltimore in the US.