The most tired cliché in political discourse, which I myself reserve only for instances in which it’s merited, is to compare your political opponents to Hitler and/or the Third Reich.
“The Nazis did this, X did something that is vaguely, through logical contortions, similar, therefore X Is Hitler,” it goes. It’s very predictable and, almost always, indicates a grasping at straws by the side making the argument that is out of other means of arguing.