In the NY Times' reporting on the Trump-Kim potluck charade, there's more than a little evidence of an enormous waste of time — except for unilateral concessions by the United States, which seem to be Trump's negotiating style:
If anything, the White House moved closer to Pyongyang’s language, saying it sought complete, verifiable and irreversible denuclearization "on the Korean Peninsula" — a clause that North Korea interprets as potentially requiring the United States to scale back troop deployments there or to shrink its nuclear umbrella over two East Asian allies, South Korea and Japan. Secretary of State Mike Pompeo insisted the administration’s policy had not changed.
As for the waste of time …
On Monday evening, the White House announced that Mr. Trump planned to leave Singapore on Tuesday evening, after a single day of talks with Mr. Kim. It was not clear whether the move was tactical — to put pressure on the North Korean leader — or reflected a growing recognition on the part of the White House that the two men may have little to talk about.
It would shock if their sit-down lasted more than a few minutes, unless Kim does all the talking. Trump is so characteristically unprepared about all he can do is gaze into Kim's eyes and try to read his soul. Kim, no doubt, will do the same, but both will be disappointed as they stare into a soulless abyss.
If nothing else, the Times story is worth reading for its inadvertent humor.
What remained unclear is whether [the concluding joint] statement would include timelines for North Korea to give up its weapons, a detailed accounting of the scale of the North’s nuclear program or a reference to sanctions.
In other words, what remains unclear is virtually the entirety of this charade.