While the U.S. economy is struggling, U.S. corporations aren't.

A third of the way through the second-quarter reporting season, earnings at companies in the Standard & Poor's 500-stock index are the highest in four years, according to S&P analyst Howard Silverblatt, who predicts the second half will be even stronger. Yet there is little indication that the strong results will jump-start the U.S. economy and get the millions of Americans idled by the recession back to work.

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