If you're talking about the F-22, no, they haven't really been deployed. I think the Air Force does have about a dozen of them, but thankfully the plug was pulled on funding. Yes, I said luckily, because the war with the USSR it was made to fight will never happen, it didn't even really work at it's assigned roll, and against a target like North Korea wouldn't be any more effective than the US's standing arsenal. Which in this case would be mostly cruise missiles, B-1s, and eventually B-52s flying at stratospheric altitude.
I don't why the North Korean military is being batted around like they rely on Flintstones technology. They buy tons of weapons from Russia and China, and you can be damn sure that if the United States actually was involved in another war there, China would hand them all the classified specs they've stolen, as a lab-test of their weapons against US designs. Or just for shits and giggles really, it is China after all. The countryside is littered with weapons already - automated radar-guided SAM launchers and anti-tank guns, and probably more land mines than anywhere else on Earth. Then factor in the tunnel networks riddling the mountains and God only knows what other traps a bored and paranoid military can devise, and manned by a fanatically loyal universal militia very familiar with both the terrain and evading the notice of military authorities. Compared to the rest of the real world, North Korea is basically the Final Boss of invasion scenarios, precisely because they've been ruled for sixty years by paranoid dictatorships who've made a national industry of preparing for a Western-backed invasion.