But there you have it, DaftPunk - when your parents came, the country wasn't so crowded, there were so many jobs that needed doing, in the health srvice, in transport etc etc, and STILL there were the signs: no blacks, no Irish. And blatant racism.
Because undernath all the rationale, many people are quite simply, racist. Some people may join the BNP because they believe that immigants are responsible for the strain in the NHS (which has nevertheless continued to offer an increased range of extra services to more people, year, on year, more sophisticated procedures, more succesful treatment...), some people may well be out and out racist. There will be many who are both.
My parents live in an area which suffers typical 'rural deprivation'. A German co moved into one of the towns and turned a dissused plant of some kind into a massive paper mill. To get the workforce they needed they advertised locally (huge unemployment) for managers at all levels, on the grounds that managers would need to spend 2 weeks at their existing plant in Germany, full pay, all expenses paid, obv, training. My Mum's friend works in a hair salon, and listened to person after person say they would refuse to go to germany - didn't want to leave home, didn't want to go where 'krauts' lived, blah blah. Then it was in the local paper: company had had to bring in managers from outside the area and from Germany.
THAT is a parochial mindset that leads to the 'drawbridge up' mentality of the BNP - England good, everywhere else bad, let's not be adventurous and make change, lets not be open minded and accept change, and let's cut off our noses to spite our faces'.