Manipulate indefinitely?

If the corruption is at the top of U.S. and international banking, government and regulatory agencies, and they can manipulate the price of PMs (paper sales, margin hikes, etc.), why can't they continue to do so indefinitely? Is it wishful thinking that reign of the EE will come to an end? What events are sure to end it? I'm not asking rhetorical questions for dramatic purposes, I'm just a stacker trying to understand the actual mechanics and looking for sources of information. Thanks.