I have another theory:
Since the Snowden revelations, a lot of people who previously were blissfully unaware of the level of domestic spying (and lying) being perpetrated by our government have suddenly had a wake-up call and are making their displeasure known to various elected officials. (Not everyone, mind you -- just a few minutes ago I opened an e-mail from an old friend who is an ex-Seabee, who thinks Snowden should be emasculated, eviscerated, evaporated, and generally hung out to dry.) But, in general, I think it's fair to say that significant numbers of Americans don't like realizing that they are being spied upon, and then lied to about said spying.
If we can accept that as a possibility, then isn't it convenient to have a timely, "credible" threat ("we know they're going to hit somewhere, we just don't know exactly where or when") to use as justification for all this spying and lying?
But I'm sure the timing is pure coincidence ...