Has nobody else noticed another piece of historic spam in this topic?
I think that's the second one I've spotted that was years old (in this case it was posted almost 8 years ago)
Anyway, I always found the "Defend Bucky" mission rather easy. Usually I just shoulder-barge in, grapple & throw whoever's left fighting Bucky to change their focus - then laugh as Jimmy Hopkins goes all Chuck Norris on their rears.