Updates:

10:48 - The Wall Street Journal reports in a news alert that the U.S. will seek a UN Security Council resolution authorizing military strikes in Libya. Meanwhile, a Reuters "flash" report declares the "Libyan army will stop its operations on Sunday to give rebels a chance to surrender." The source is Al Arabiya.

 

Original Post (9:41 AM ET):

In recent weeks, even as the Libyan rebels, the Arab League, the U.K., and France came out in support of imposing a no-fly zone over Libya to ground Muammar Qaddafi's Air Force, the U.S.--already fighting wars in Iraq and Afghanistan--refused to commit to the idea.

That's all changed in the last 24 hours, as the prospect of Qaddaf's forces dealing a bloody, knockout blow to rebels in their headquarters of Benghazi loomed ever larger.

On Wednesday, Qaddafi's son, Saif, warned that the regime's forces were "almost in Benghazi" and that military operations would be over "within 48 hours," while the Libyan army informed the city's residents to leave "rebel-held locations and weapons storage areas" by 6pm Eastern Time so that forces could arrive "to cleanse your city from armed gangs." The deadline passed without an assault, prompting one Benghazi resident to label the regime's tactics "psychological warfare," according to Reuters. More recently, though, government planes bombed a nearby airport and Al Jazeera reports that there have been some casualties.

Whether or not Qaddafi's forces carry out their threats on Benghazi, the U.S. appears to believe the situation on the ground has deteriorated enough to necessitate a change in tone. Late Wednesday, U.S. ambassador Susan Rice expressed support not only for a no-fly zone--which has "limitations in terms of protection of civilians at immediate risk"--but for broader military options to protect civilians, including air strikes on Libyan tanks and heavy artillery. That same day, Secretary of State Hillary Clinton called the Arab League's support for a U.N.-authorized no-fly zone a "turning point" in U.S. decision-making since it showed the alliance was willing to take "action against one of its own." The U.N. Security Council is expected to vote on a resolution for military intervention in Libya late on Thursday. The measure will likely face opposition from Russia and China.

But just how far is the U.S. willing to go? That remains unclear, The New York Times notes, given the administration's "deep aversion to being entangled in another war and its clear calculation that Libya does not constitute as vital a security interest to the United States as other countries in the region, notably Egypt or Saudi Arabia. Some administration officials voiced the hope that the mere threat of military action could prompt Colonel Qaddafi to show some restraint."

Elsewhere in Libya, violent clashes between Qaddafi's forces and rebels continued in Ajdabiya in the east and Misrata in the west, with conflicting reports about who controlled each strategic location.