Making his case for the U.S. involvement in Libya, President Obama sounded a cautious tone, in a speech needed to explain to an American public that isbut divided about the goals of the mission -- that the U.S. should not be afraid to act but that the burden of action should not be America's alone. The mission, he said, was to avert a humanitarian disaster.
On the same day, the U.N. Secretary General, Ban Ki-moon, who is at the London summit on Libya Tuesday, said the United Nations - which imposed the no fly zone mandate and authorized the use of force - has seen no evidence of a ceasefire in Libya or of any steps by the country's authorities to fulfill their obligations under Security Council Resolutions aimed at protecting civilians.
"We have serious concerns about the protection of civilians and respect for human rights and international humanitarian law," he said.
The secretary general's report on Libya, given to the U.N. Security Council late last week, asserted that Libyan authorities have repeatedly claimed that they have instituted a ceasefire, including in a call to him by the prime minister but, he said, "We see no evidence that is the case. To the contrary, fierce battles continue in or around the cities of Ajdabiya, Misratah and Zitan, among others. In short, there is no evidence that Libyan authorities have taken steps to carry out their obligations under Resolutions 1970 or 1973."
The secretary general expressed deep concern about a possible humanitarian crisis in Libya, despite Security Council steps to isolate and sanction Qaddafi's inner circle, who have been ignoring warnings to stop a military campaign attack their own people. He said that up to 250,000 refugees and migrants could be displaced by the fighting in Libya and he was worried "about the protection of civilians, abuses of human rights and violations of international humanitarian law and the access of civilian populations to basic commodities and services in areas currently under siege."
And, although Mr. Obama spoke of American values, strategic interests and the limits of the mission, it is, nonetheless, a rare moment in time that the U.N. Secretary General sounds a more impassioned and urgent note than an American president on an issue involving U.S. military action.
But overall, the president received support at the U.N. for the message that conveyed the purposes of American involvement with some skepticism by analysts about what happens next. He made a point of differentiating Libya from American involvement in Iraq: there would be no U.S. involvement in regime change. That would be up to the Libyan people.
Unlike the second U.N. vote on Iraq, under the Bush Administration, which sought support for military action, and failed, Mr. Obama was able to garner a U.N. Security Council Resolution that imposed tough sanctions and authorized the use of force to protect a civilian population. The two U.N. Security Council Resolutions (1970 and 1973) referred the case of Libya to the International Criminal Court and imposed the no-fly zone. All three of the Council's African members, South Africa, Nigeria and Gabon, voted in favor of the Resolution.
Unlike the Saddam Hussein period, when the oil-for-food scandal undermined economic sanctions, Mr. Obama was able to make economic sanctions stick. In a record period of time, billions of dollars of Qaddafi's funds have been frozen.
He said, "We then took a series of swift steps in a matter of days to answer Gaddafi's aggression. We froze more than $33 billion of the Gaddafi regime's assets. Joining with other nations at the United Nations Security Council, we broadened our sanctions, imposed an arms embargo, and enabled Gaddafi and those around him to be held accountable for their crimes."
What the president did not do in his speech, which may have dismayed some critics, was address the percolating crises in Syria, Yemen, Iran and Bahrain. Mr. Obama appeared constrained to describe what the action means for the future. Does the United States find a way to support regime change in Iran or Syria?
Yet, a discussion of the "Obama Doctrine," as some are calling it, did not appear to be the purpose of the speech. It was intended to point out what an unusual point in time that the U.S. found itself in.
Although there has been some wavering, the decision to impose a no-fly zone was supported by the Gulf Cooperation Council, the Arab league and European allies, including France and Britain, which appeared even more eager than the U.S. to begin the military campaign.
A joint statement by French President Nicolas Sarkozy and British Prime Minister David Cameron on Monday said, "Tomorrow in London, the international community will come together to support a new beginning for Libya. A new beginning in which the people of Libya are free from violence and oppression, free to choose their own future."
They said, "Following an appeal by the Arab League to take action to protect the people of Libya...the United Nations Security Council passed an historic resolution to protect civilians from the violence unleashed by Qadhafi's war machine."
The president's words reflected the caution of the events at hand and appealed to the American public and NATO allies' view of the post-war responsibility to protect civilians. What happens next will depend on events on the ground.
Pamela Falk is CBS News Foreign Affairs Analyst and an international lawyer, based at the United Nations.