Libyans show their support for the rebellion after Friday prayers near Green Square in Tripoli. Francois Mori/AP hide caption

itoggle caption Francois Mori/AP

A trader reacts after the close of trading in the Nasdaq 100 Index pit on the floor of the CME Group on Aug. 8 in Chicago. Stocks plummeted after Standard & Poor's downgraded U.S. debt. M. Spencer Green/AP hide caption

itoggle caption M. Spencer Green/AP