Magic dirt is a derogatory term for the theory that where a person lives determines the person's psychological characteristics. It is a variant of the "blank slate" theory.
Such views are often applied to migrants, both between countries and within countries, with an assumption being that migrants (or their descendants) from poorly functioning areas/populations will assume the characteristics of well-functioning areas/populations by migrating.
A similar theory is that moving students from poorly functioning schools to well-functioning schools will cause the students to become well-functioning.
Civic nationalists often explicitly or implicitly support the theory.
Supporters of the magic dirt theory and mass immigration often point to earlier immigration of Europeans to the United States, arguing that this was successful, despite sometimes initial opposition to some immigrant groups, and claiming that the same thing will happen in the future. This ignores the very different nature of many current immigrant groups with, for example, the cultural and genetic differences being much larger. Black-White differences and problems are still extensive, despite Blacks having been freed from slavery for many generations. Another difference is that the earlier European immigration occurred when tax-paid welfare systems were much smaller or absent.
School desegregation and desegregation busing in the United States did not eliminate Black-White achievement differences, as expected by desegregation proponents.
See Islamization and anti-Islamization: Opinion surveys of Muslims on surveys finding unchanged or increasing support for sharia and other not politically correct views by Muslim immigrants and their descendants, rather than decreasing support as often assumed by liberals.
See Race and intelligence: The genetics or not debate: Socioeconomic factors on race, IQ, and socioeconomic factors.
See Race and intelligence: The genetics or not debate: Immigrants on race, IQ, and migration.
Another criticism is that the magic dirt theory is an example of the sociologist's fallacy.