WASHINGTON (AP) — President Barack Obama on Wednesday imposed a $500,000 cap on senior executive pay for the most distressed financial institutions receiving taxpayer bailout money and promised new steps to end a system of “executives being rewarded for failure.” Obama announced the unusual government intervention into corporate America at the White House, with Treasury Secretary Timothy Geithner at his side. The president said the executive-pay limits are a first step, to be followed by the unveiling next week of a sweeping new framework for spending what remains of the $700 billion financial industry bailout that Congress created last year.