Perhaps the scariest thing is their plan to collect and store all data on all of your activities, then retroactively mine it

I would even go to say that the NSA already has files on all major politicians in the US and therefore can threaten anyone (including the president) to release something the public would not like (extra-marital affairs, pretty common among politicians, but could be many other things too) and therefore easily coerce the politicians to avoid any significant reform of their mandate.