Yesterday’s terrorist activity in Spain and ISIS’ thus far unsubstantiated public claim that the attackers were “soldiers of the Islamic State” has once again thrust the group to the forefront of the world’s attention—a place ISIS has occupied for years now. Indeed, in the summer of 2014, I was asked during a congressional hearing whether the Islamic State (also called ISIS), which had recently seized Mosul and was threatening Erbil, could capture Baghdad. Then deputy director of national intelligence, I replied that the intelligence community did not think such a takeover was plausible given what we knew about ISIS’ personnel strength and the overwhelming Iraqi military….