as Ernie points out, there is usually some grievance that leads to people looking at what are regarded as extreme organisations. Problem is that the mainstream see it as easier to ignore and chastise rather than attempt to understand and deal with.
The perception is that there has been a huge amount of immigration over the last few years, there are no jobs. Now the simple thing is to say throw the immigrants out and the jobs will be there. Read papers such as the Mail and it is clear that it is the non white-anglo-saxon-british causing lots of the problems.