Dubya said today that the preemptive war doctrine stays: The U.S. reserves the right to attack any nation that might pose a threat to it through that nation's possession of biological, chemical or nuclear weapons.

An excerpt:

The long-overdue document, an articulation of U.S. strategic priorities that is required by law, lays out a robust view of America's power and an assertive view of its responsibility to bring change around the world. On topics including genocide, human trafficking and AIDS, the strategy describes itself as "idealistic about goals and realistic about means."

THE NATIONAL SECURITY STRATEGY FACT SHEET: THE PRESIDENT'S NATIONAL SECURITY STRATEGY National Security Strategy Overview (whitehouse.gov)   National Security Strategy of the United States 2006 (pdf File)

The strategy expands on the original security framework developed by the Bush administration in September 2002, before the invasion of Iraq. That strategy shifted U.S. foreign policy away from decades of deterrence and containment toward a more aggressive stance of attacking enemies before they attack the United States.

The preemption doctrine generated fierce debate at the time, and many critics believe the failure to find weapons of mass destruction in Iraq fatally undermined an essential assumption of the strategy -- that intelligence about an enemy's capabilities and intentions can be sufficient to justify preventive war.

In his revised version, Bush offers no second thoughts about the preemption policy, saying it "remains the same" and defending it as necessary for a country in the "early years of a long struggle" akin to the Cold War. In a nod to critics in Europe, the document places a greater emphasis on working with allies and declares diplomacy to be "our strong preference" in tackling the threat of weapons of mass destruction.

"If necessary, however, under long-standing principles of self defense, we do not rule out use of force before attacks occur, even if uncertainty remains as to the time and place of the enemy's attack," the document continues. "When the consequences of an attack with WMD are potentially so devastating, we cannot afford to stand idly by as grave dangers materialize."

Such language could be seen as provocative at a time when the United States and its European allies have brought Iran before the U.N. Security Council to answer allegations that it is secretly developing nuclear weapons. At a news conference in January, Bush described an Iran with nuclear arms as a "grave threat to the security of the world."

In a letter introducing the new strategy document, Bush also said, "We fight our enemies abroad instead of waiting for them to arrive in our country. We seek to shape the world, not merely be shaped by it; to influence events for the better instead of being at their mercy."

Some security specialists criticized the continued commitment to preemption.

"Preemption is and always will be a potentially useful tool, but it's not something you want to trot out and throw in everybody's face," said Harlan Ullman, a senior adviser at the Center for Strategic and International Studies. "To have a strategy on preemption and make it central is a huge error."

A military attack against Iran, for instance, could be "foolish," Ullman said, and it would be better to seek other ways to influence its behavior. "I think most states are deterrable."