"There is a long border, that makes it hard to control. We have beefed up places along the border to try to stop" the flow, he said.

When told that his policy didn't seem to be working, Bush insisted, "It’s working a little better.

"They're doing a pretty good job down in Arizona, which is the main border crossing. ... I think there's a thousand more border patrol agents along the border. We’re modernizing border techniques, we’re using better surveillance methods to stop this crossing at the border."

The president contended, however, that illegal immigration was driven primarily by the economic realities of the region.

"If you can make 50 cents in the interior of Mexico and five bucks in the interior of the United States, you're coming for the five bucks," he explained.

"I happen to believe the best way to enhance the border is to have temporary-worker cards available for people," he said. "I think the long-term solution for this issue on our border is for Mexico to grow a middle class. That's why I believe in NAFTA."

When warned that "a lot of people are not going to like that answer," Bush told O'Reilly, "Well it’s a, a truthful answer."

Editor's note: