Exclusive: Cheney Cites 'Major Success' in Iraq, Says U.S. Has Hit 'Rough Patch'

By some estimates, the war will end up costing Americans anywhere between $2 trillion and $4 trillion.

Citing an insurgency that lasted longer than anticipated, Cheney said five years ago there was no way "to estimate what the final cost would be."

"In any major enterprise or conflict like this once it starts, you cannot predict with precision exactly what course it's going to follow," Cheney said, emphasizing he's "not sure how" the aftermath in Iraq could have been better predicted.

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'We Have to Get It Done'

Asked how long it will continue, Cheney said, "You do it as long as you have to until you get it right. You don't quit because it gets hard."

Pressed for a timeline, Cheney stressed, "I don't know how long it's going to take. I do know we have to get it done. And if it takes a long time. That doesn't make it any less worthwhile. This has been a hard-fought, difficult, challenging thing for us to do, but we kept at it because it's the right thing to do."

Quitting two years ago would have meant chaos, Cheney said. "Certainly, it would have been a much worse situation from the standpoint of the Iraqi people."

"It is hard. It has been difficult. No question it's been costly, in terms of treasure and life but it's worth it. And we are going to get it right," Cheney said.

Economy's 'Rough Patch'

Cheney also touched on the current state of the economy, admitting, "We're clearly going through a rough patch." But the Bush administration has not said the United States is experiencing a recession.

Cheney said that the downturn can be blamed in part on natural economic cycles, pushing back on the idea that any one of the administration's specific policies were responsible for it.

"We've had, prior to that, 52 months of uninterrupted economic growth," he said. "Now, of course, we've got problems in the housing industry, mortgage-backed securities and so forth that have created problems that we're having to deal with."

Taking Stock of '08

Supporting Republican presidential nominee Sen. John McCain, R-Ariz., in November, Cheney said he'd do everything he could to help the Arizona senator but held back his thoughts on the Democratic race.