Why is some of the best gallows humor in action movies? Because the stakes are high. There's a real chance the characters might die here, making their attempts to laugh off the danger all the more admirable. Which might be why wisecracking in action movies eventually fell out of fashion. As the 80's action heroes became effectively indestructible, the gallows element dropped away and the humor just became corny and cliched...

Outstanding observation, Debbie. And it makes me think about the prototype, for me, of the wisecracking hero: WWII Royal Air Force pilots, and the whole "smoke me a kipper, I'll be back for breakfast!"-schtick. They knew the odds were they wouldn't come back from every single run, so the stakes were high, the bravado was higher, and the gallows humor was omnipresent. The antithesis of the indestructible movie hero. Your formula of high-stakes gallows humor was really the engine that drove so much of the repartee in M*A*S*H, too. I'm going to spend a lot of time thinking about how raising the stakes affects the characters and raises the humor. Thank you!