That’s what Michael O’Hanlon, of the Brookings Institution wants.  He thinks a continued, but greatly reduced alliance would be a useful tradeoff for northern Korea’s elimination of its nuclear weapons and nuclear weapons development program along with a reduction in its conventional military forces.  Aside from the utter naivete of the suggestion that northern Korea would reduce its conventional capability along with giving up its nuclear capability—or especially in light of that cessation—one comment at the end of his piece really illustrates the naivete of his idea.

The heavy Army brigade now in Korea might be transformed into a light brigade, better suited for peacekeeping missions.

Peacekeeping missions are wholly incapable of keeping the peace unless they’re fully capable of fighting.  Unfortunately, peacekeeping missions are incapable of fighting a serious enemy (and police forces are better suited for dealing with unserious enemies—criminals).  A light brigade on that peninsula would not be a peacekeeper, it would be a target.