Arnoldthecat, I spent my formative years on a rough estate in South Wales and am unlikely ever to go near a montessori nursery.
The thing that ripped the economic and social fabric out of where I grew up, as well as big swathes of the north-west and north-east, was the dismantlement of heavy industry in the 80s and 90s. This had nothing to do with racism but the policies of the tories, and subsequently new labour who did too little to fix things.
If you go to the Welsh valleys, or Teeside, or any of these places, you'll see they have gone (further) to shit despite being almost exclusively white British. It's true that in some of the bigger cities lots of immigrants have moved into these areas, but that's because they can afford to live there.
In other words, there are immigrants in the areas because the areas have gone to shit, not the other way round. Of course they're not going to live in fucking Altrincham or Didsbury, because they don't have a pot to piss in.
It's another example of (particularly right-wing) politicians shafting ordinary people, then holding their noses and pointing at the foreigners.