President Barack Obama is telling Chinese students that the greatest threat to the United States' security is terrorist networks such as al-Qaeda.
Obama on Monday met with students in Shanghai and said al-Qaeda has crossed from Afghanistan into Pakistan and is in contact with other organizations. Obama says the United States must stabilize that part of the world and reduce the power of extremist networks.
Obama says the groups are small in number but are dangerous because they have no conscience. Obama says terrorist organizations armed with nuclear or biological weapons could kill hundreds of thousands of people with just a few individuals.
Obama says the United States is trying to give civilians greater hope and limit the influence of leaders like Osama bin Laden.