How long will it take before the United States can safely withdraw most of its troops from Iraq?

"I think it will take years," Brent Scowcroft, the native Utahn who was the national security adviser to both Presidents Ford and George H.W. Bush, told the Deseret News on Monday. "From the time we went in, it may be a decade."

Scowcroft was speaking because of the release of a new book that he co-wrote with Zbigniew Brzezinski, the national security adviser to President Carter. The book is called "America and the World: Conversations on the Future of American Foreign Policy."

A review of the book, which came out Monday, will be in this Sunday's Deseret News.

"The fundamental reason for this book is to push for a stronger element of bipartisanship in foreign policy," Scowcroft said in a telephone interview. "We have a wide number of very difficult problems in the world. They are difficult enough to solve by themselves without shouting at each other as Democrats and Republicans." Scowcroft, a retired Air Force lieutenant general who was born and raised in Ogden, said he and Brzezinski found they agreed on most key areas. But even when they disagreed, they could be thoughtful and analytical to point out a range of possibilities.

One of those disagreements is on troop withdrawal in Iraq — even though both Scowcroft and Brzezinski spoke out against the latest war there before the invasion and correctly predicted many of the problems that came afterward.

Brzezinski says in the book that "Iraq cannot be put together if we continue to be there" and argues for withdrawal within about 16 months to allow Iraq to work out problems by itself.

But Scowcroft told the Deseret News, "I think what our objective should be is to leave in place an Iraq that would be an influence for stability rather than chaos and conflict. ... You can't judge that based on the calendar. You base it on the situation on the ground. It will be a slow process."

He said the Iraqi army is making quicker progress than he had expected in its ability to handle security needed for Iraq to work out its political future without violent chaos, but it still largely depends on U.S. forces for intelligence, support, logistics "and all the things that make an army effective."

"We can withdraw as the situation on the ground improves. I am getting increasingly optimistic that we are on a decent path there," he said.

While Scowcroft says the book is designed mostly to look toward the future, a chapter in it looks at "how we got here." Scowcroft in it talks a bit about why he opposed the latest war in Iraq and why in the first war he did not push to take Iraq and overthrow Saddam Hussein.