On Wednesday, British Foreign Secretary William Hague hailed the Libyan rebels' "increasing legitimacy, competence, and success".
On Thursday, with impeccable timing, it transpired that those rebels might have murdered their top military commander.
If Abdul Fattah Younes did indeed die at the hands of soldiers he nominally led, it would be little surprise.
Gen Younes was a man with many enemies.
He had defected to the rebels only after four decades of friendship with and service to Libyan leader Col Muammar Gaddafi.
Rumours of his lingering ties to the regime seemed to have caught up with him after he was summoned by a panel of judges in Benghazi.
That came on the heels of severe criticism of his military leadership for a series of territorial losses early in the uprising.
The furious reaction from members of Gen Younes' Obeidi tribe, amongst the largest in eastern Libya, indicates the resurgence of tribal divisions hitherto papered over by the strenuous efforts of the broad-based National Transitional Council (NTC).
These will not shatter the NTC or lead to the collapse of Benghazi, but they point to longer-term problems for the anti-Gaddafi rebels.
The first irony is that the assassination of Gen Younes will scarcely affect the military campaign. For a short period some months ago, the rebels' military command was anyway bifurcated between the defector Gen Younes and the war hero and long-time US resident Colonel Khalifa Hifter.
The NTC denied that these divisions mattered. And yet, shipments of rifles would never make it to official units, orders from Gen Younes would be amended by Col Hifter, and bitter debates over strategy and tactics got in the way of decision making.
Col Hifter or another commander will likely step into the breach and Gen Younes' death might, perversely, simplify things. But even if it doesn't, it might not matter much.
This is because Libya's revolution has already fractured into hundreds of semi-independent fronts, each driven by local fighters soldiering in local conditions.
The most important battlefield successes of the past month, those in the western mountains and around Tripoli, have had virtually nothing to do with Gen Younes' operational nous.
That much should be clear from the widespread looting and executions - essentially, war crimes - by rebel soldiers in western towns like al-Qawalish and al-Awaniya, actions patently incompatible with the commitment to military professionalism and legality professed by the NTC.
As if to underline this detachment, between formal leadership and the various theatres of operations, even as news of Gen Younes' death was trickling out from Benghazi, major advances were being made in the plains south of the capital and near the border with Tunisia.
Seizures of the towns of Tekut, Hawamid, and Ghazaya now place rebel forces in a strong position to sever supply lines into Tripoli, hastening what they hope will be an organic urban uprising.
Just as Misrata was liberated from within (though not without some assistance from the east), this war will likely be won more than 800km (500 miles) away from the political wrangling of Benghazi and the frustrating stalemate around the oil town of Brega.
But the second irony is that Gen Younes' death threatens to unpick the NTC's credibility and cohesion at exactly the moment of its latest diplomatic triumph - fresh endorsement from Britain, the last major rebel ally to recognise the opposition as Libya's legitimate representatives.
The NTC, though lax in investigating and stopping battlefield transgressions by its own soldiers, has earnestly sought to include representation from across Libya's regions and tribes. It is now at pains to placate Gen Younes' Obeidi tribe and counter the regime's narrative that the revolution is simply a tribal, rather than democratic, movement.
That narrative is exaggerated propaganda, intended to discredit the opposition. But the resurgence of at least some tribal and factional animosities has been apparent for months.
In the west, it is evident in the revenge attacks on the pro-Gaddafi Mashaashia tribe. In the east, it was clear from the spontaneous shows of force by the Obeidi tribe after Gen Younes' death, including the establishment of roadblocks in Benghazi and an attack by tribesmen on the hotel where the NTC had just given a press conference.
These latent divisions were well known. They underpinned the British and American decisions to refrain from directly arming the opposition. But as deeply embarrassed as the rebels' international backers will be at these episodes, they see no alternative but to work through the NTC, having invested so much in the removal of Gaddafi, and absent any other viable partners.
The concern that emerges most sharply from this incident is not so much that the NTC will splinter before Tripoli falls, but that it might do so after.
If it struggles to represent the full spectrum of political forces in a transition period, in the face of armed factions demanding political sway, Gen Younes' killing might not be the last political assassination amongst the self-described Free Libya Forces.
Shashank Joshi an Associate Fellow at the Royal United Services Institute (RUSI), a defence think-tank in London, and a doctoral student of international relations at Harvard University.