"The idea of there being a massive attack in the United States like 9/11 is unlikely, in my view," Biden said Wednesday night on CNN's "Larry King Live." "But if you see what's happening, particularly with al Qaeda and the Arabian Peninsula, they have decided to move in the direction of much more small bore but devastatingly frightening attacks."
The attempted Christmas Day bombing last year in Detroit represents the types of threats the country is more likely to face, he said. Biden added that the Obama administration, however, has handled the threat well.
"I've been really impressed with the success we've had, building on the last administration, in dealing with these," Biden said.
In terms of threats to stability abroad, Biden said Iran becoming a nuclear state was "a real concern, not an immediate concern."
More pressing, he said, is the situation in Pakistan.
"It has nuclear weapons that are able to be deployed," the vice president said. "It has a real significant minority of radicalized population. It is not a completely functional democracy in the sense we think about it. And so that's my greatest concern."
Meanwhile, Biden said that progress in Iraq "could be one of the great achievements of this administration."
"You're going to see 90,000 American troops come marching home by the end of the summer," he said. "You're going to see a stable government in Iraq that is actually moving toward a representative government."
Biden also touched on topics including politics and the economy. He said that he expects to see a net creation of jobs every month starting this spring. He also said his former opponent, former GOP vice presidential candidate Sarah Palin, is an "engaging person" with a "great personality" even though he does not agree with everything she says.