Obama Limits U.S. Policy for Nuclear Weapons

The Cold War ended more than two decades ago, and American nuclear policy finally caught up with history Tuesday. Under the new policy adopted by the Obama administration, the gravest threat is no longer all out nuclear war but the chance that just one weapon will fall into the hands of a terrorist or rogue state, CBS News National Security Correspondent David Martin reports.

"Given al Qaeda's continued quest for nuclear weapons, Iran's ongoing nuclear efforts and North Korea's proliferation, this focus is appropriate and indeed essential, an essential change from previous reviews," Secretary of Defense Robert Gates said at a news conference.

Nuclear Posture Review Report (PDF)

The new policy comes before President Obama heads off to Prague Wednesday to sign a new agreement with Russia to reduce the number of nuclear warheads on both sides.

Nations have always viewed nuclear weapons as weapons of last resort, but for a terrorist they would be the first choice, which accounts for a truly alarming prediction by Graham Allison of Harvard University.

"It is more likely than not within the next five years there's a successful nuclear or biological terrorist attack somewhere in the world," Allison said.

For the first time ever, the new policy limits the circumstances under which the U.S. would resort to nuclear weapons, assuring nations which do not have them and do not try to get them that they have nothing to worry about. But when it comes to nuclear wannabes like North Korea and Iran or terrorist groups like al Qaeda, American policy is just as threatening as it always was.

"All options are on the table when it comes to countries in that category," Gates said.

Stopping the spread of nuclear weapons is a first step toward Mr. Obama's ultimate goal of eliminating them, but he is bucking some powerful history. The number of countries with nuclear weapons has gone from one to nine in the past 65 years.

"The world is telling us by their behavior that whereas we think nuclear weapons are less important, everybody else thinks they're more important," said Thomas Donnelly of the American Enterprise Institute.

Secretary of State Hillary Rodham Clinton called the new policy a milestone, but if the goal is to eliminate nuclear weapons it will be a very long road.

More on Obama's Nuclear Policy

New, More Restrictive Nuclear Policy Unveiled
Rudy Giuliani Calls Obama Nuclear Policy "Left-Wing Dream"
Obama Goes Nuclear
China Leader to Attend U.S. Nuke Summit
Obama Announces Nuclear Weapons Reduction Treaty With Russia
Historic Treaty Cuts Nuclear Arms By 25%