Even as NATO foreign ministers failed to come together Thursday on a plan for ramping up the alliance’s air campaign in Libya, the country’s rebels warned of an impending blood bath in the western city of Misrata if NATO does not take out the Qaddafi regime’s tanks and artillery firepower.

And as if to thumb his nose at NATO’s impact in his country so far, leader Muammar Qaddafi chose the very hour of the NATO ministers’ meeting in Berlin to drive around Tripoli in a convertible vehicle, waving to onlookers and pumping his fist defiantly.

NATO officials are acknowledging that the three-week-old Libya campaign needs more and different kinds of aircraft, in particular if the alliance is to carry out the “protection of civilians” portion of its mandate.

IN PICTURES: Libya conflict

The NATO commander of the Libya operation, Admiral James Stavridis, made a plea at the Berlin meeting for more precision fighter jets to join the mission. While it appeared no commitments were made, NATO Secretary General Anders Fogh Rasmussen said he was “optimistic” that several countries would “step up to the plate” by Friday’s close of the ministerial gathering.

All eyes were on the US, since it is the US that has the kinds of aircraft Admiral Stavridis is seeking. Yet while Secretary of State Hillary Rodham Clinton called on the ministers to maintain “our resolve and unity,” she gave no indication the US was prepared to reverse course and provide the kind of airpower that would return it to a lead role in the air campaign.

The US started out in the lead of the effort to establish a no-fly zone over Libya, deploying forces that President Obama said at the time were “unique” to the US and essential to stopping Colonel Qaddafi’s use of airpower against rebel forces and civilian targets.

In the days leading up to NATO’s two-day ministerial meeting this week, France and Great Britain complained of inadequate participation and airpower in the NATO-lead operation, and suggested the alliance could fail in its task to protect Libyan civilians without a return of US airpower.

Libyan rebels on Thursday said rocket attacks on Misrata – the only city in western Libya under partial rebel control – had killed at least two dozen people. They predicted a “bloodbath” in the coming days if NATO fails to stop Qaddafi’s offensive.

Secretary Clinton seemed to want to acknowledge the rebels’ warnings when she told her NATO colleagues that “Qaddafi is testing our determination.” Or perhaps she had seen the Libyan television footage of the Libyan leader riding around Tripoli in sunglasses and a green safari hat.

Clinton reiterated what she said is the alliance’s goal, which is “to see the end of the Qaddafi regime in Libya.” But she also suggested that the US would not be ratcheting up its military contribution to achieve that goal, saying the international coalition assembled on Libya “must also intensify our political, diplomatic, and economic mission to pressure and isolate Qaddafi and bring about his departure.”

IN PICTURES: Libya conflict