The controlling feature for this prior isn't "willingness to kill own citizens" or "publicity stunt" but "massively risky". "Massively risky" is actually an incredible understatement. We're talking about people already at the top of the social hierarchy risky death and eternal shame for them and their families in hopes the hundreds of people part of the conspiracy keep quiet and that no damning evidence of a remarkable complicated plot is left behind.

The government's willingness to kill it's own citizens, such as it is, less often carries over to civilians and even less often carries over to rich white people on Wall Street. And for something that has help shaped the country... well remarkably little has changed in the direction that administration wanted to things to go. Indeed, why in all those years of waning popularity, wouldn't they try something like it again (maybe foil the attempt this time). If they're so powerful why not get someone else elected President?