Maybe the problems of race is affecting more people so they are more aware of the problems caused by immigration and our multi cultural society.
My mother lived in Hillingdon, West London (she died last February) which has a high immigrant population due to London airport being in the area.
She got a newsletter every so often from the local council about issues in the area.
The last one she showed me beofre she died was about the number of people in Hillingdon who were building sheds or garages (or other buildings) at the bottom of their garden and then renting them out to immigrant families, asylum sekers, illegal immigrants etc.
These buildings have no proper sanitation, running water etc.
The council have to keep raiding these houses and demolishing these outbuildings.
Now you say you joined AB 8 years ago, but did that sort of thing happen back then? Probably not, and if so very rarely.
And as has been said, we had the three bombers from Birmingham a week so back, and the fact Birmingham was still on "high terror alert".
So more and more we see the impact of our lax immigration impacting our day to days lives, so people ARE going to get more upset and angry.
The problems of our debt, jobs being lost, prices rising and so on are all going to fuel people's anger.
And when we see 2.4 million people are on the dole we all begin to wonder why we keep letting people in the country when there are not even enough jobs for the ones already here.
Why daughter and boyfriend are trying to emigrate to Australia (she has had enough of this country). But even though they both have skills needed in Australia they still have to go through hoops to get a visa, have their skills assessed in this country, AND pay money to get a visa. And even then they cannot get in unless csomebody over there agrees to sponsor them with jobs.
Yet over here we seem to take anybody and everybody, even if they cant speak English, have no skills, have nothing to offer the country, and even threaten to blow us up.
No wonder people are getting annoyed.