It's the corporate overlords (or, as President Eisenhower -- a Republican and Army General FFS! -- put it, the "military-industrial complex").
If you can figure out how to dislodge them, you could be well on your way to something resembling democracy along popular mis-conceptions of what that might actually mean (and surely, that does not include a mercantilist republic that goes around the world enforcing favourable trade "agreements" by sheer military force. Anyhow, those days are rapidly ending, totally eclipsed by China).
Suffice to say, it won't be easy, painless or quick.
EDITED: 7 May 2011 19:25 by DSMITHHFX