I found 3 articles recently that are crying out to be written into some sort of uber-post and if I could write, I'd knock this out. Since I can't, you're stuck with this.
First is this article at everyjoe.com which talks about the types of nations and what holds them together. Executive summary; There are 2, the ethnic nation made up of an ethnically homogeneous population like Japan or Korea, and the civic nations made up of multiple ethnicities and held together by a common civic outlook such as Rome and the United States. The article notes that the civic nations are harder to hold together as divisions in the civic outlook among the population can weaken the nation. The example cited is Germany which some years back was a civic nation that seemed to be holding together fairly well but is now being strained by massive immigration of Muslims to the point that PM Merkel is now calling for a drastic slowdown or even a halt.
Good article, good background. Read this one first. Then go to wnd.com for an article on how Sweden is feeling the bite possibly harder than Germany, noting a sudden interest in personal armaments there. This is in keeping with an upsurge in personal defense all over Europe as the most readily available arms, shotguns, are suddenly in very short supply which has led a Turkish manufacturer to run afoul of import rules in their haste to supply the market.
An article associated with the wnd piece here at gatestone institute describes Sweden as descending into anarchy, at least in selected locations, and describes the result as a night-watchman state -- each man is on his own. An interesting turn of phrase if ever I heard one and perhaps one destined to become more popular in the near future.
Interesting to note that the influx of Muslims in Europe is spurring the same reaction there as "sudden jihadi syndrome" is spurring here, i.e. a sudden increased interest in self defense. It is also, I believe spurring an interest among Muslims in instituting reform within the community. I can certainly sympathize as moderate Muslims certainly do not wish to be seen as ticking time bombs by a heavily armed and suspicious populace within which they're trying to live.