Exactly, in Orwellian societies there should always be an enemy to justify more control and surveillance. Even better if they are on the run for a while then later you can pull them out for the 2 minutes of hate. Wars on Terrorism, terror cells, terrorists in caves, Eastasia/Eurasia, and on and on are used to beef up defense, tracking and police force through fear.

I was watching a BBC documentary on Vikings and they cited multiple occurrences of early British leaders using the threat of Viking invasions in order to influence the populace. But the number of occurrences of invasions actually taking place in historical records are nearly non-existent.

So to further this point, the threat doesn't actually have to be tangible or to actually have taken place to be well utilized.

Considering the vast number of tangible, actually occurring, problems that are being neglected there seems to be a long history of poor resource allocation in human culture thanks to fear.