Here's an article that raises a should-be-obvious question that hasn't occurred to many Americans: If the NSA can spy on an Angela Merkel, then why can't it spy on domestic politicians?
Did Obama spy on Mitt Romney? As recently as a few weeks ago if anyone had asked me that question I would have consigned them to a right (or left) wing loony bin. Today, the only loonies are those who think the question unreasonable.
Did the NSA use the information they gathered on Mitt Romney and other political candidates for political purposes? Probably not. Will the next president or the one after that be so virtuous so as to not use this kind of power? I have grave doubts. Men are not angels.
That said, I would point out that most people within the American intelligence community vote Republican. I've heard lots of stories about the election-year bumper stickers one tends to see in the CIA parking lot, and I doubt that the situation is much different in Fort Meade.
But that's the problem with granting too much power to the executive branch of government. Even if you find the current executive tolerable, the same power will one day go to someone you cannot abide.