U.S. stocks tumble as Fed sows fear and confusion

``Michael O'Rourke, chief market strategist at JonesTrading, said the Fed's window for tightening is now likely shut. He said the central bank is paralyzed by fear of deflationary effects from a strengthening dollar and a potential rollover of the global economy. "Anyone expecting asset-price gains to be driven by monetary policy is missing the fact that there is no monetary policy. The Federal Reserve is a spectator on the sidelines, and it just forfeited its opportunity to uphold the illusion that it is in this game," wrote O'Rourke in a note.''