The NSA won't tell Congress how many Americans it's spying on

You would think there would be some more tangible action Congress could take, given its constitutional mandate to provide oversight of the executive branch, but you would be wrong. In theory, they might repeal FISA, but it's pretty clear that's not going to happen. We've been doing this dance for three congressional terms now and this is basically all that ever occurs.It's especially weird since the NSA's charter is for foreign intelligence, so the answer to "how many Americans are you spying on?" should really be zero. But we all know that's not true, thanks to documents leaked by a whistleblower who is unable to enter the country on pain of immediate lifetime imprisonment.If the current election cycle in the US has proven anything to me, it's that the American 'democracy' is fundamentally broken, down to its very core. How on earth can the NSA just refuse to answer these questions?