They will pass from the scene to the relief of many and mourned by few. They will be remembered by with fear and loathing for their dishonesty, corruption and immorality. People will emerge who will tear down their few "achievements" and rebuild our world - not without struggle and not perfectly.
We have it in us. We can do it. In 20 years, people will wonder what the hell was wrong with the world then. Of course, the lessons learned will be forgotten & we'll go through it all again with different faces and different issues. History teaches this but each generation must find its own answer.