There are numerous arguments against immigration, including the displacement of the national culture, reduced labor quality and high crime rates. When it is illegal immigration, the question of rule of law also comes into play.
One of the major arguments against immigration is expounded by anti-immigration author Lawrence Auster in piece for the Social Contract Press. He explains that immigrants bring their own culture, language and values that ultimately displace the culture, values and traditions of their new country of residence. The resultant rise of multiculturalism diminishes the pride that citizens have in their history, which they come to see as irrelevant. The moral fiber of society weakens as citizens have to embrace an ever-greater level of tolerance in the face growing cultural diversity.
There are also economic arguments against immigration. The Federal Reserve Bank of San Francisco observes that the large migration of unskilled laborers lowers quality standards in the job market. And because immigrant workers are typically willing to work for lower pay than the average wage, their presence in the labor pool has the effect of reducing salaries for everyone else.
Immigration also leads to increased crime. Immigrant groups tend to live in concentrated geographic areas. Concentrations of poverty-stricken immigrants with little formal education and limited familiarization with the language are breeding grounds for criminals.