US can't act alone in the world: Obama

New York: President Barack Obama declared on Saturday the United States cannot act alone in the world and pledged to shape a new "international order" as part of a national security strategy to seal his break with Bush-era policies.

Setting out his vision for keeping America safe as it fights wars in Afghanistan and Iraq, Obama stressed international engagement over predecessor George W Bush's "cowboy diplomacy" and signaled his likely repudiation of Bush's justifications for pre-emptive war.

"The burdens of this century cannot fall on our soldiers alone, it also cannot fall on American shoulders alone," Obama told graduating cadets at the US Military Academy at West Point. "Our adversaries would like to see America sap its strength by overextending our power."

Obama's speech previewed his new National Security Strategy -- required by law of every US president -- to be released next week.

His words suggested it would deviate sharply from Bush's go-it-alone approach that placed US power over diplomacy in the aftermath of the September 11, 2001, attacks.

Bush in 2002 laid out the "Bush Doctrine" asserting the right to wage pre-emptive war against countries and terrorist groups deemed a threat to the United States, part of a policy he called a "distinctly American internationalism."

What followed was the 2003 US-led invasion of Iraq despite the lack of formal UN authorisation. Since taking office last year, the Obama administration has fueled speculation that the president's new strategy will officially back away from that controversial concept.

Though Obama did not explicitly revoke the Bush Doctrine at West Point, he emphasised the need to prevent attacks through multilateral cooperation with intelligence agencies "working seamlessly with their counterparts to unravel plots."

He also asserted that the only reason US forces continued fighting in Afghanistan was because "plotting persists to this day" there by al Qaeda militants behind the September 11 attacks on the United States.

MUSLIM OUTREACH Obama said the United States must strengthen existing alliances, build new partnerships and promote human rights worldwide as it pursues a strategy of global leadership.

"We are clear-eyed about the shortfalls of our international system," he said. "But America has not succeeded by stepping out of the currents of cooperation." "We have to shape an international order that can meet the challenges of our generation," he said.

Obama's call for global cooperation was also a message to NATO allies in Afghanistan to stiffen their resolve when questions are being raised about their commitment to the war.

Obama kept up his outreach to the Muslim world. While accusing al Qaeda of distorting Islamic values, he avoided using terms like "war on terror" and "Islamo-fascists" that Bush employed regularly and which alienated many Muslims.

Obama has been widely credited with improving the tone of US foreign policy but is still struggling with challenges ranging from nuclear standoffs with Iran and North Korea to sluggish Middle East peace efforts.

Critics say some of his efforts at diplomatic engagement show US weakness. Obama warned of "difficult days ahead" in Afghanistan to break the momentum of a resurgent Taliban but expressed confidence that US-led and Afghan forces would succeed. When Obama visited West Point in December, he unveiled his plan to send 30,000 more troops to Afghanistan coupled with a promise to start bringing forces home in July 2011.

The buildup is considered vital to a US-led offensive in coming months in the Taliban stronghold of Kandahar that could weigh on the success or failure of Obama's war strategy. Obama spoke just over a week after hosting Afghan President Hamid Karzai at the White House, where they presented a unified front in a bid to show their differences were behind them.

But that did not mean the Obama administration had suddenly gained full confidence in Karzai as a credible partner. Obama's challenge is to convince a skeptical American public and Congress that the war is worth fighting and funding and to keep Afghanistan from becoming a political liability in a congressional election year.