The primary problem, is that freeze, fight and flight are instinctive reflexes, pretty much at the lizard-brain level. The amount of training, deep programming really, needed to create a serious behavioral change at that level, is non-trivial and repetitive. This is pretty much what a large component of what martial-arts (and related rescue/military) training is: Creating deeply ingrained "body knowledge" that overrides these reflexes. To get the person to "react" without really thinking too much about it. So getting the general public to take that type of training upon itself is probably non-doable without a major cultural change.

Culture itself is a major component of how people react. Take the crazy Israelis, for instance, who typically run TOWARDS the site of an attack.

BUT I refuse to accept the basic premise of the "problem" that FEMA is addressing, without seeing some hard studies: What percentage of "mass-casualty" events are actually "ongoing" past the initial event. In how many cases was their, in retrospect, an actual NEED to secure the area? Or is this just typical pussy-footing?