Drills are great camouflage for false flags.
The real LEOs can’t tell who is part of the drill and who is a real perp.
Works great on air traffic control, too... :-)
False Flag event's have some of these in common:
- drill conducted at the same time
- reports of multiple shooters soon after the event
- perpetrator everyone knew was a psycho
- it's immediately announced the school will be torn down
There might be a few more, I've read the list before.