Black Ops 2: Can you RAISE the difficulty?

i'm playing through the campaign and i wanted to see something i missed and restarted the campaign and set it to recruit just so i could get to the part i wanted to see. after that, i restarted it and tried to set it back to hardened, bit it won't let me raise the difficulty! i tried the rewind function and it kept me at easy. and replaying the mission only leaves you off at the end. it doesn't continue the campaign!

IS there a way to raise the difficulty? if so, how??? or are we screwed if we lower the difficulty?!

I guess you are pretty much screwed. I don't like it either. Specially since you can't get the "best" ending when playing recruit mode. Kind of unfair if you ask me. I realized this when I couldn't get the CIA memo. It wasn't there. That kind of ticked me off.