Why specifically them? The article mentions the NSA as well, which has done its fair share of domestic spying. As a taxpayer, it doesn't really matter to me how those lines are drawn, how budget/intel/personnel flow between them, what they call a mass surveillance program in any given decade, etc. In my short life, they've failed to prevent an attack, failed to prevent two major wars of false pretenses, failed to foresee, much less prevent, a major Russian invasion...
Has the intelligence community, regardless of agency, actually prevented any recent wars? Or why do you believe that "spying prevents war"?