Mayor Bloomberg says that Americans may be seeing the beginning of a massive economic slide, New York Post informs. In his weekly appearance on WOR radio, Bloomberg said the federal government must balance the budget and restore confidence in order to avoid a downhill slide. If it doesn’t, he said, “This could be the start of the decline of the greatest superpower, the greatest economic engine ever created.” Bloomberg gave a speech in Washington earlier this week calling on Congress and the president to allow George W. Bush’s tax cuts to expire at the end of 2012.