Guilt by Association is the attempt to discredit an idea based upon disfavored people or groups associated with it. This is the reverse of an Appeal to Authority, and might be justly called "Appeal to Anti-Authority". An argument to authority argues in favor of an idea based upon associating an authority figure with the idea, whereas Guilt by Association argues against an idea based upon associating it with disreputable people or groups
Blacks, Hispanics, jazz musicians, beatnics, hippies, Soros - the arguments haven't changed in seventy years, they just point the finger in a different direction.