First, I would just like to say that I have a problem with seeing the Britons as a “race”…
Secondly, just 1,6% of the global population have mobility and the opportunity to immigrate, and it is a process that carries economic, mental and emotional costs – its not something so easy that everyone can do. However, many people do not have the standard of living available to most people living in Britain or have other pressures that compell them to make these decisions, each case is individual, they are human beings and not just a group of people that are “threatening” the country/society where they live, by treating them as such you are dehumanising them. Immigrants are individuals with families and stories of their own and the right to be treated with respect.
Maybe you should be directing your criticisms to the companies who employ them with often informal/semi-exploitative working conditions (referring to the afore mentioned Poles ).
Our immigration policies are not perfect and the govt/local communities need to work together to ensure that there is integration and that communities do not remain segregated (which often happens in the face of discrimination) as well as the development of effective policies to address the social issues in marginalised/disadvantaged communities (no matter what ethnic mix they are made up of).
The answer though is NOT through the instrumental use of the immigration issue for political leverage as many of those social issues exist and would still exist in areas where there is a low incidence of immigration.