The danger is that an insider from the NSA could seize power in the United States.
Sound farfetched? Vladimir Putin, a former KGB officer, took Russia from a democracy to a kleptocracy powered by his old KGB buddies. Someone from the NSA can do something quite similar in America.
Here are the steps:
1. The president succumbs to the temptation to use information gleaned from NSA surveillance to blackmail his opponents. You can imagine the phone call that results:
"Senator, I know you are planning to vote against the President's bill tomorrow, but just think of the consequences. We know you have nothing to hide, but your nephew has been looking at some sketchy websites; if this gets out he could go to prison. And your brother has been caught on tape to his accountant doing some very creative tax avoidance that could land him in jail as well. Oh, and one of your major donors has been doing some insider trading. So think carefully about how you vote tomorrow."
2. After a while, the NSA will tire of just pulling the strings for the president and want to put their own man in the White House. The NSA can try to blackmail all the good candidates out of the race. If that fails they can target the donors. If word leaked out that donors to a candidate were being
personally investigated by various governmental agencies, donations would dry up—along with any chance of winning an election.
The concentration of power in the NSA is incompatible with democracy. Vote for candidates who support reigning in domestic surveillance, unless you really admire what Vladimir Putin has done in his former democracy.