Does an increasing migrant presence contribute to political radicalization of societies?

Yes. In my opinion, political radicalization is caused by fear of loosing national identity and traditional values. Instead of being aimed to the affirmation and reevaluation of their traditional values, that fear is aimed against migrants and other minorities by various prohibitions.

Fresh example is Denmark where parliamentary majority have been agreed on “ghetto package", laws that regulate life in 25 low-income and heavily Muslim enclaves, saying that if families there do not willingly merge into the country's mainstream, they should be compelled. (New York Times).

Burk ban laws are introduced in Austria, France and Belgium. In several countries in Europe radical right-wing parties with politicians against migrants, have larger and larger support, in some of them (Denmark, Austria, Hungary) they won the elections. These examples also tell the story of political radicalization.

When you know who you are and your identity, no one can threaten or jeopardize it. Especially not other people or cultures.