Qusair capture changes Syria conflict dynamics
The defeat of Syrian rebel forces who have now withdrawn from their positions in the town of Qusair represents a significant victory for the government and its Hezbollah allies.
Potentially it changes the dynamics of the conflict - something that will have political and diplomatic ramifications. It also increases the likelihood of a more persistent spillover of the fighting into Lebanon.
Many of the key battles in the Syrian civil war have focussed on supply routes and the key towns that sit astride these vital arteries.
Qusair is a case in point - its location is crucial for both sides.
It is a focal point for arms supplies coming into Syria for the rebels from Lebanon via two main routes: the first coming up through Lebanon's Bekaa Valley, and the other coming from further west, from Tripoli and the coast.
But the town is also close to important supply lines for the government forces.
Qusair is important in terms of controlling the road to Homs to the north-east. The road from Damascus to Homs is a central armature for the Syrian regime. Homs is the crossroads that connects to the Alawite heartland on the the Syrian coast.
So the strategic importance of Qusair is not in doubt.
What is unclear for now are the wider implications of its loss for the rebels. It adds to a growing sense over recent weeks that the government forces are gaining ground.
The implication is not that they will win - but rebel forces as presently constituted cannot gain a victory either.
So the prognosis is for a divided Syria to battle on with neither side able to force a decisive outcome.
The longer the fighting continues so the greater the risk of regional contagion.
The battle for Qusair has highlighted the importance of fighters from the Lebanese Shia movement Hezbollah, which has openly waded into the fray on the side of President Bashar al-Assad.
This is a high-stakes gamble for Hezbollah, explicitly reinforcing its links to the Syria-Iran axis and - in the eyes of many Arab-watchers - linking it firmly to the Shia-cause in what is fast becoming a struggle with significant sectarian overtones pitting Sunni against Shia.
Hezbollah has in the past sought to present itself as a Lebanese national movement. Now it is engaged in an inter-Arab civil war.
Hezbollah's image inside Lebanon has suffered.
The fear now is that the violence in Syria will spill over into Lebanon.
In a BBC interview, the military commander of the Free Syrian Army, Gen Selim Idriss, has spoken of his desire to confront Hezbollah fighters inside Lebanon.
Up to now there have been sporadic gun battles and some rocket fire in Lebanon linked to the conflict over the border. But any attempt to open up a Lebanese "front" in the fighting risks the wider regional conflagration that so many Western diplomats fear.
With Lebanon in turmoil again and Hezbollah potentially weakened, Israel, too, might be drawn into the fray - eager to settle scores with the Shia movement.
Given Israel's concerns about the supply of sophisticated weaponry from Syria to Hezbollah, it is easy to see a scenario involving further Israeli air strikes on arms convoys that escalates into a wider engagement.
It is precisely these concerns that are driving diplomatic efforts to convene a peace conference in Geneva.
But for now the diplomatic machine seems to be turning in a void.
The Qusair offensive is unlikely to make the Syrian government more conciliatory.
And as the struggle continues, Western powers are faced with a range of unsavoury options with some arguing for the arming of the rebels or even for more explicit military action against the Syrian regime.