The strategy also calls for US engagement with "hostile nations," closer relations with China and India, and a focus on strengthening the US economy.

Several of Obama's top advisers are discussing the new strategy in a carefully-orchestrated rollout in Washington.

Hillary Clinton, the US secretary of state, gave a speech at the Brookings Institution on Thursday afternoon in which she called democracy and human rights "central" to the strategy.

Clinton also called America's high debt levels a threat to national security.

"We cannot sustain this level of deficit financing and debt without losing our influence, without being constrained about the tough decisions we have to make," Clinton said.

General James Jones, Obama's national security adviser, will discuss the document at Washington's Foreign Press Club.

Break from Bush

Analysts in Washington have described the document as a clear break from former president George Bush's two national security strategies, issued in 2002 and 2006, which endorsed unilateral military action and spoke of the threat posed by "Islamic extremism".

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 Obama describes a coming era in which US will have to learn to live within its limits

Obama's strategy calls for the US to work within international institutions, like the United Nations and Nato, though it calls for significant reforms to those world bodies.

"An international architecture that was largely forged in the wake of World War II is buckling under the weight of new threats," the document says.

In a speech previewing the strategy on Wednesday, John Brennan, Obama's counterterrorism adviser, said the strategy reflected a shift in al-Qaeda's tactics. He pointed to several recent failed attacks against the US - the Times Square bombing attempt, and the failed Christmas Day airplane bombing - as examples of al-Qaeda's "less sophisticated" tactics.

"As our enemy adapts and evolves their tactics, so must we constantly adapt and evolve ours, not in a mad rush driven by fear, but in a thoughtful and reasoned way," Brennan said.

Rule of law

Obama's new strategy also repeatedly makes mention of "American values," and pledges to uphold the rule of law.

"Advancing our interests may involve new arrangements to confront threats like terrorism, but these practices and structures must always be in line with our Constitution," the document says.

But the new strategy fails to explain how the commitment to the rule of law squares with some of the administration's most controversial national security decisions.

Obama has accelerated the pace of drone strikes in northwest Pakistan's tribal regions, for example, over the official objections of the Pakistani government. And it continues to use military commissions, rather than civilian courts, to try many detainees accused of terrorism.

"If they seriously believe that demonstrating our commitment in practice to civil liberties and the rule of law is vital to our national security... how can they reconcile that with the way drone strikes are being used... with the use of military commissions, and so forth?" wrote Marc Lynch, a professor at George Washington University, in an analysisof the new strategy.