One has to assume that highly intelligent conspirators will find extremely clever ways to hide and disguise their activities, objectives, and agenda. We must not be too quick to close the book on history and take events at their face value, for this is precisely what conspirators would have us do. They would like nothing more than to be able to use or create some shocking event in order to veil something more deeply sinister. It's the basic principle of camouflage. That way, they can slip their pernicious plot in under the radar.
For anything shocking that is revealed, there's likely something even more shocking left unrevealed.