If Hackworth is on point for US foreign policy the wise thing to do is to move as fast as you can in an equal and opposite direction.
He was wrong in 1991, he was wrong about Afghanistan, he's wrong about Iraq and he's wrong now.
We may not have cause to remain in the Korean peninsula now days but to shag now because the North Koreans have waved their nuclear capability, courtesy of the Clinton/Carter Morons for Appeasement, in our face is a decidedly bad idea.
Don't want to defend Hackworth character, too many flaws. He was not wrong in 91 "it's a six minute war", Jury is still out on Afghanistan, and who cares what the marxist, cult-of-personality political whores in DPRK and/or elsewhere think? Planning people on all sides of that equation know better than to read something into that. Vietnam was a stated pullout with no intention of returning, there is no analogy here. This is a simple case of not letting world opinion prevent the US from doing what is best for the US