President Trump may have chosen the right way during summitYou’ll probably see references to this being called a “failed summit” in the news. But this isn’t the worst-case scenario; the worst-case scenario would be if we made serious concessions on sanctions and other issues in exchange for unverifiable promises about North Korea’s nuclear-weapons programs.
(Assuming that the DPRK didn't have alternate ways to underminde those sanctions; so far, China didn't let Kim down, and I guess that Xi planned to do so in the near or far future)By walking away, Reagan increased the pressure on Gorbachev and the Soviet regime — and with just a few years, it ceased to exist. The Soviet Union ended not with a bang, but with a whimper.
But there is no serious pressure upon the DPRK. Actually, nothing has changed for the DPRK, pre-Trump, and also not during his presidency. Kim has played him for the time being, and surely is going to continue after this summit and those to come.
(I didn't read what they had to say on Michael Cohen because Cohen's statements during the hearing haven't been verified yet. He either lied, or he didn't, but as long as we don't know, it's worthless to comment it. This applies for everyone,)