9/11 Checkmate

Listen up, buttercup! This joke is dark. Like, "lights-out, hide-your-teddy-bear" dark. The joke refers to the 9/11 attacks and uses "checkmate," a term from chess, to imply that the attacks were a decisive victory against the United States. It's funny because of how horribly unfunny it is. You're laughing at tragedy because you're edgy, not because it's actually funny.