Because of a general improvement in the national standard of living in many countries, nationals no longer want to do menial or dirty work. They tend educate their children to be able to take on office jobs or skilled trades. This results in a demand for immigrants who are willing to do the menial or dirty work. Because of their lack of education and knowledge of industrialized countries, they accept low payment and consequently find themselves living in slums and shanty towns with inadequate facilities. They may also be undernourished, living in severely overcrowded conditions which may prevent families from joining them, thus destroying their family life. Where families are allowed to enter, educational facilities for the children may be inadequate. Many of such immigrants are from developing countries and are of a different race, thus creating racial, colour and class tensions. Because of the dependence of families at home on their income, they are unwilling to return to their own countries, where their status and incomes would be even less. If a high unemployment occurs in such a situation, the conflict increases and the immigrants are accused of stealing the rightful work of the national population or causing a drain on social security. They may be denied the right to join trade unions which would raise their status. Industrialists prefer to use immigrants for menial work rather than machinery which cannot be laid off in a slack period. As many immigrants enter illegally, firms can exploit them and pay less than the minimum wage.
The problem is greatest mainly in western Europe, but also exists the USA, Canada, and some newly industrializing Gulf countries, where non-European immigration has been increasing with post-war industrialization and general improvements in the national standard of living. Due to the world economic crisis, many countries have recently stopped all work-related immigration and now are interested primarily only in family reunion immigration, except in a few cases of specialist work which are generally highly skilled and highly paid (although in the case of the computer industry in the USA, it is reported Russian and Indian software programmers are being given jobs over Americans at half the wages). Industrialists in France, Germany and the Netherlands find it difficult to think of the future of their firms without a large flow of new immigrant workers to do routine jobs of low status that Europeans do not want to do. France and Germany already have over 3 million immigrant workers, mainly from the Middle East and North Africa; and interracial conflict is marked by killings and riots, particularly in large ports.