Re: American CEO sleeper?
"from their own families as well as the un-expected opponents."
FTFY.
For modern examples, look at North Korea or (less bloodily) the political party of your choice. (The UK Tories look like the best example right now, despite Momentum's best efforts within Labour.) The plain fact is that once you've eliminated the possibility of change from without, you can be certain that you now face a threat from within.
Smart people might reckon that this is a good argument for remaining open, because it is much easier to see an external threat building up, so you have more time to make yourself safe.