DavCrav: "... then say they didn't know about IS seems a bit weird."
The larger point is here of course the failure of proper intelligence reaching the desks of policy makers and ideally entering their minds. Despite all the high tech cowboy spying and drone flying, enormous intelligence errors appear to occur more as rule than exceptions, for example: Iraqi WMD, linkage between Iraq & Bin Laden, 9/11 hijack & crash threat, airspace readiness, Iranian nuclear bomb and consequences of meddling with Libya and Syria for regime change.... all disastrous advices and reports if not meddled with by politicians of course - hard to say at times.
The moral of that story is that computers, hacked or not, like communications, hacked or not, rarely make a government or a human being for that matter one ounce wiser. Any seasoned IT professional should already know that! If anything, computers and modern communications dumb down, overreach, distract and inflate in spades. Especially politicians seems to be vulnerable - even more so than teenagers!