Powell: Terrorism Not Greatest Threat to U.S.

On the upside, he didn't say carbon emissions are the top threat, so he's preserving a little bit of credibility. But he's way off base claiming we don't have enough immigrants coming into the country, be they legal or illegal.

He really needs to get out more often.

Colin Powell: Terrorists are not greatest threat to nation

"What is the greatest threat facing us now? People will say it's terrorism. But are there any terrorists in the world who can change the American way of life or our political system? No. Can they knock down a building? Yes. Can they kill somebody? Yes. But can they change us? No. Only we can change ourselves. So what is the great threat we are facing?"

Powell adds, in an interview with Walter Isaacson, that to improve its image in the world, the USA should focus on welcoming newcomers. He takes on the immigration debate that has become a hot-button issue in the presidential race:

"America could not survive without immigration," he says. "Even the undocumented immigrants are contributing to our economy. That's the country my parents came to. That's the image we have to portray to the rest of the world: kind, generous, a nation of nations, touched by every nation, and we touch every nation in return. That's what people still want to believe about us. They still want to come here. We've lost a bit of the image, but we haven't lost the reality yet. And we can fix the image by reflecting a welcoming attitude -- and by not taking counsel of our fears and scaring ourselves to death that everybody coming in is going to blow up something. It ain't the case."