Hasnt happened yet and we've had a lot worse then BO and Clinton. Think US Grant or Buchananan. Worst we'll ever see is someone get the boot. I don't think we'll ever see a President in prison. Maybe we can just send them into exile in France next to all other third world dictators that get run out of the country.
This from one of the guys here who actually voted
for bho.

Assassinations, like Kennedy's are messy, too public (sends the message, though), too many people involved, too many chances for leaks, too many people to disappear, etc. Physical assassinations are the very archetype of complex, almost uncontrollable systems.
Character assassination works wonders. The leftoids own the press, most of the courts, and most of the Fed .gov, as well as many state and local .govs as well. So, should a patriot - should someone who wants to restore the Constitution and eliminate the elitism, eliminate the entitlements - actually get elected POTUS, they will find a way to impeach him to eliminate him.
klintoon was a bad joke, he almost muffed being POTUS. It took all of the Fed .gov powers to save his sorry behind and only impeach him, without the conviction.