The executions of sacco and vanzetti in the 1920s demonstrated the

Increase in Nativist attitudes.

Explanation:

Italian immigrants Nicola Sacco and Bartolomeo Vanzetti in 1920 attempted robbery at a shoe factory and murdered two people. Both were put on trial and executed. The outcome of the executions resulted in nativist attitudes toward working-class immigrants. The immigrants ruined their reputation after the capture of both the Italian men because they believed to be the destroyer of American society through anarchists.