You know who really learned that the hard way?
Gaddafi
Here’s a guy that saw Saddam go down, figured he was next, so he VOLUNTARILY gave up his WMD program hoping to avoid the same fate. We airlifted nuclear materials out of the country.
Obama takes the Presidency, and he, Hillary, and the Euros figure they can loot Libya, so Gaddafi gets taken down and murdered despite having done that.
And we wonder why Kim is difficult to negotiate with.