It seems to me that, regardless of whether or not there is true efficacy in the actions of hostile intelligence, domestic intelligence will always see it as a t

It seems to me that, regardless of whether or not there is true efficacy in the actions of hostile intelligence, domestic intelligence will always see it as a threat. Given that perspective, I think a government's desire to spy domestically comes (at least in part) from a desire to counter that threat. So I kinda think the boogeymen exist but, to your point, they are not necessarily as effective as they would like to be.