Dictator Kim turned out to be just Trump's kind of guy.
The agreement they made doesn't commit either side to much.
Some rebuke the bully for giving Kim a kind of legitimacy and getting
no practical concessions in return.
However, denying Kim legitimacy was doing nothing to win any
concessions from him, so the leverage that the US has forfeited was
not worth much. Changing to a friendly tone might achieve some
progress toward peace, and that progress could make possible concrete
deals that are impossible today.
Or it might backfire and trigger a resumption of hostilities when the
expectations of either side are disappointed.
History of US-North Korea Deals Shows Hard Part Is Making Them Stick.