Sociologist Joe Feagin distinguishes four different categories of discrimination. He uses the term for harmful action intentionally taken by a dominant-group member against a member of a subordinate group, with or without the support of other members of the dominant group in the same social context.

Isolate discrimination

Explanation:

Based on the scenario being described within the question it can be said that the term being mentioned is known as Isolate discrimination. Like mentioned in the question this is one type of discrimination in which an individual in the dominant group attacks either emotionally or physically another member of the subordinate or minority group.

world war i had a devastating effect on german-americans and their cultural heritage. up until that point   german-americans, as a group, had been spared much of the discrimination, abuse, rejection, collective mistrust experienced by so many different racial and ethnic groups in the history of the united states. indeed, over the years, they had been viewed as a well integrated and esteemed part of american society. all of this change with the outbreak of war.