He sought major changes to Social Security and immigration laws, but both efforts failed. The wars in Afghanistan and Iraq continued, and in 2007 he launched a surge of troops in Iraq. The Bush administration's response to Hurricane Katrina and the dismissal of U.S. attorneys controversy earned wide coverage, and his second term saw a drop in his approval ratings. With President Bill Clinton term-limited, the Democrats nominated Vice President Al Gore for president. Bush's campaign emphasized their own candidate's character in contrast with that of Clinton, who had been embroiled in the Lewinsky scandal.