“They’re called ‘watermelons’ for a reason.”
I’ve always thought of them as traditional Martians.
Thin green skin stretched over an alien red goo and completely comfortable with the elimination of however much humanity required to reach their goal of universal misery.
I just point and say "watermelon" (which actually is advanced when compared to my typical single syllable remarks)....And if asked to elaborate I'd just say, 'a commie covered with the veneer of green'...
But your description was better - particularly regarding the goal to inflict universal misery upon the unwashed masses.