A chump is a specific kind of fool - specifically, someone who believes and supports
the person who is making fun of them, making the foolishness that more foolish. It's one thing to be called an idiot, but to be a chump, you have to call
the person who is calling you an idiot a great person
because you are so clueless you do not realize the person has called you an idiot (or taken advantage of you in some way).
The
Republicans who talk about law and order and serving their country are chumps for supporting
Donald Trump, who loves their support while
laughing hysterically behind their backs because they are such fools! Trump would never fight for his country - that's a job for chumps!