(03-28) 04:00 PDT Washington ---

Nine days after opening a bombing campaign in Libya, President Obama addressed the nation Monday in a prime-time televised address to sell the war to a skeptical Congress and a public puzzled by his decision to launch a third war in the Islamic world.

The president laid out a new Obama doctrine, a middle way between regime change and refusing to intervene: "We should not be afraid to act," Obama said, "but the burden of action should not be America's alone."

Obama said the mission has prevented a civilian slaughter by Libyan strongman Moammar Khadafy and a potential refugee crisis that could destabilize neighboring Egypt and Tunisia, where autocratic regimes have just toppled. He said failure to act would have destroyed Western credibility.

"To brush aside America's responsibility as a leader and, more profoundly, our responsibilities to our fellow human beings under such circumstances would have been a betrayal of who we are," Obama said. "Some nations may be able to turn a blind eye to atrocities in other countries. The United States of America is different. And as president, I refused to wait for the images of slaughter and mass graves before taking action."

He acknowledged that "America cannot use our military wherever repression occurs. And given the costs and risks of intervention, we must always measure our interests against the need for action. But that cannot be an argument for never acting on behalf of what's right."

But he said an attempt to overthrow Khadafy by force would go too far. "To be blunt, we went down that road in Iraq," Obama said.

He said the United States will hand off command Wednesday to the North Atlantic Treaty Organization, of which the United States is the leading partner. Obama also promised aid and the return to Libyans of $33 billion in frozen assets. He did not discuss an end date for U.S. involvement.

Obama spoke from the National Defense University in Washington, deliberately avoiding the Oval Office setting traditionally used by presidents to announce military actions.

Despite sharp criticism from both parties, Congress is unlikely to mount a serious challenge. The House and Senate plan hearings Thursday, but the wars in Iraq and Afghanistan proved the difficulty Congress has in devising a coherent policy to oppose a president in war.

Congress has mainly been demanding that Obama clarify the goal, exit strategy and cost of the Libyan bombardment, rather than voicing outright opposition.

Reps. Zoe Lofgren and Mike Honda of San Jose, Barbara Lee of Oakland and Lynn Woolsey of Petaluma have accused Obama of violating the Constitution and the War Powers Act by entering into a war without congressional assent.

Woolsey said the only control Congress has is over funding and so far the administration contends it can pay for the operation from its current budget.

"I'm very concerned about the consequences of rushing into war without understanding the situation on the ground or the exit strategy," Woolsey said. "Maybe that will come. But we learned some very harsh lessons through the last two ill-advised wars in Iraq and Afghanistan."

Two leading California Democrats, Sen. Barbara Boxer and House Minority Leader Nancy Pelosi of San Francisco, both of whom sharply criticized the wars in Afghanistan and Iraq, have lent Obama muted but important political support, citing humanitarian aims.

Boxer said Obama "reminded the country tonight of why it was critical for the international community to take action to prevent the mass slaughter of innocent men, women and children."

Obama insisted in 2007 that no president has constitutional authority to "unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation."

Defense Secretary Robert Gates said Sunday that Libya is "not a vital interest to the United States." The White House has refused to call the air attacks a war, using such terms as "kinetic military action."

Obama's effort to sell a new war and limit the U.S. role in it, "requires a certain amount of fancy footwork," said Charles Kupchan, a former national security official in the Clinton administration. "If this is in fact a war worth fighting, then why is it we need to be backpedaling? There are answers to that, but it requires nuance."

Libya's military is weak compared to Egypt's or former Iraqi dictator Saddam Hussein's, posing a chance for the United States to take a side in the "Arab Spring" of democratic revolutions, at less cost than might be paid elsewhere, Kupchan said.

No matter what Obama says, "what he needs is some outcome that can be reasonably portrayed as a success and can get us out of this," said Michael Mandelbaum, author of "Frugal Superpower" and foreign affairs expert at Johns Hopkins University. "You don't want to be flying air combat patrols over Tripoli for the next nine years, or nine months or nine weeks."

The best outcome would be "for Khadafy to fall from power, and we could declare success and go home," Mandelbaum said. "Our goal is to get out."

E-mail Carolyn Lochhead at clochhead@sfchronicle.com.

Source: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/03/28/MNEG1IKVN7.DTL#ixzz1I1KOrnA7