PARIS - France and Britain have restored Europe's relevance on the world stage in forging the drive to block Libyan leader Muammar Gaddafi from crushing a revolt against his rule.
But their push for United Nations-backed military intervention carries an uncertain outcome and the price of fuelling friction with Germany and exposing the weakness of the European Union.
The initiative's chief architect is French President Nicolas Sarkozy, who was strongly, but independently, supported by British Prime Minister David Cameron.
Appalled at foot-dragging by the Obama Administration, the pair joined forces to coax the United States into supporting airborne intervention, have the policy endorsed by the Arab League and then backed by the UN Security Council. Just a week earlier, Sarkozy's political stock was in the basement, but his fast response, supported by his new Foreign Minister, Alain Juppe, is likely to win him praise at home.
At a US, European and Arab summit in Paris yesterday to allot roles in the operation, Sarkozy revived memories of the glory days when France by itself could make things move and shake.
Just as Gaddafi's tanks were entering Benghazi, Sarkozy announced at the Elysee presidential palace that, in effect, the cavalry had arrived.
"Our planes are already preventing air strikes on the city," Sarkozy declared.
"With our partners, especially our Arab partners, we will move to protect the civilian population from the murderous folly of a regime that, by killing its own people, has lost all legitimacy. We are intervening to allow the Libyan people to themselves choose their destiny. They cannot be deprived of their rights through violence and terror."
British Prime Minister David Cameron struck a Churchillian tone: "And so the time for action has come. It needs to be urgent. We have to enforce the will of the UN and we cannot allow the slaughter of civilians to continue."
Juppe described the UN vote modestly as "a collective victory, but first and foremost a victory for the UN". He emphasised that the UN resolution was for aerial intervention and barred ground troops.
"The key was an interesting combination, with the US not trying to take a political lead, whilst the Arab League did," noted Michael Clarke, director of the Royal United Services Institute, a British think-tank.
"This circumstance created an atmosphere where a British/French push for a carefully worded resolution suddenly found some traction at the 11th hour."
He and others, though, warned of some hefty practical problems ahead.
On the military side, the allies have the task of policing a vast country from the air and ensuring they target only Gaddafi's forces involved in the fighting.
If the opposition emerge victorious, the disparate group of allies also has to ensure there is no bloody settling of scores, and that the intervention does not leave a country permanently at war with itself - or ruled by another dictator.
"If the allies do excite such a reversal of fortune, they will face the need to see through what they are starting, something even the British, French and Americans may not have thought through very carefully," said Clarke.
Another problem is the friction between Europe's pro- and anti-intervention nations, although the rift is unlikely to be anywhere as big as over Iraq.
Britain and France were spurred not just because of Obama's perceived dithering as Gaddafi counter-attacked, but also because of the weak response of the EU's foreign policy chief, Catherine Ashton.
She had been singled out for lacerating criticism by Cameron at a summit of the 27-nation bloc the previous week.
Germany, a non-permanent member of the Security Council, abstained in the UN vote and this will add to the personal tensions between Sarkozy and German Chancellor Angela Merkel.
"They [the Germans] really screwed up," a French diplomat sighed.