Defense
This attitude can be traced back to the mythological examples 'good and bad' or 'god en devil'.
In social realms this translates into: we the pious ones, better family, or superior race, we must defend ourselves against the heathens.
Always there is the belief that the outside world is populated with 'the wicked ones', against whom we have to protect ourselves, or whom we must convert…
This is all based on the identity as an imaginable, separated form.