NEW YORK (Reuters) - President Barack Obama's job approval rating jumped 11 points to 57 percent after the killing of al Qaeda leader Osama bin Laden in Pakistan, but Americans fear another attack, polls showed on Wednesday.
A New York Times/CBS News poll showed the bump in Obama's performance rating -- which it warned could be short-lived -- but also found that more than six in 10 Americans believed the threat of extremist attacks against the United States was likely to increase.
Bin Laden, who had become the face of Islamist militancy since masterminding the September 11, 2001, attacks on the United States, was shot in the head by U.S. forces who stormed his compound in Pakistan on Monday after a decade-long manhunt.
A separate USA Today/Gallup survey of 645 adults showed that 62 percent of Americans believe an act of terrorism is either "very likely" or "somewhat likely" to occur on U.S. soil within the next several weeks.
"The current results indicate Americans are slightly more likely to be worried about a terrorist incident occurring than they were shortly after the London bus and subway bombings in July 2005, but are less worried than at the start of the Iraq war as well as immediately after 9/11," Gallup said.
While fearful that a retaliatory attack could be imminent, 54 percent of those polled by USA Today/Gallup believed the country was safer in the longer term from terrorism.
About 40 percent of respondents in that poll said they were also a lot more confident that the United States can succeed in its "war against Islamic terrorism," while 34 percent said they were only a little more confident.
Nearly half of the 532 people polled in The New York Times/CBS poll said the United States should not decrease its troop levels in Afghanistan, where the hunt for bin Laden began in 2001. Obama plans to start a withdrawal of some U.S. forces from the unpopular war in July.
The bump in Obama's ratings may not last. The New York Times/CBS poll said that former President George W. Bush received an 8-point boost after the capture of Saddam Hussein in Iraq in 2003, but that bounce evaporated within a month.
Obama's popularity had been hurt by economic woes and high gasoline prices. Voters are expected to focus again on domestic concerns crucial to his 2012 re-election prospects.
More than half of respondents in the Times/CBS poll disapproved of Obama's handling of the economy, a similar result to last month's survey.
That poll has a margin of error of plus or minus 4 percentage points while the USA Today/Gallup survey is within 5 points.