The recent disclosure of a massive domestic spying on American's cell phone records is an extensive expansion of executive authority, to say the least. Starting in the Bush administration, and massively expanded in the Obama administration, this dragnet is a tool which the administration has told us has been used to foil at least one terrorist plot.
The real story here in my opinion is the secret power grab by the executive branch. Never was this authority requested from the American people. In fact, for the longest time, it was outright denied. The Bush administration held focus on warrentless wiretapping which ONLY applied to conversations between suspected foreign terrorist sympathizers, and yes maybe American's were on the other end of the line. The Obama administration denied this program existed in public hearings, when they claimed that they were not "wittingly" collecting American phone records. It is clear now that both administrations expanded their own authority well beyond what the public was willing to accept, and denied it all the while.
Today, we live in a country where new powers can be dictated from the executive branch without the consent or even the notification of the people they govern. That is a terrifying world, not because of where it is, but where it inevitably will end. Our country has a generations long story of the great experiment called democracy, where the people decide the laws to which they will be held accountable. But this story is changing tune, to one where those who govern ultimately usurp that power from the people, and consolidate it for themselves.