We have lowered our long-term sovereign credit rating on the United States of America to 'AA+' from 'AAA' and affirmed the 'A-1+' short-term rating.We have also removed both the short- and long-term ratings from CreditWatch negative.The downgrade reflects our opinion that the fiscal consolidation plan that Congress and the Administration recently agreed to falls short of what, in our view, would be necessary to stabilize the government's medium-term debt dynamics.More broadly, the downgrade reflects our view that the effectiveness, stability, and predictability of American policymaking and political institutions have weakened at a time of ongoing fiscal and economic challenges...