While it is certainly good news that Syria's Deputy Oil Minister has defected to join the year-long revolt against the regime of Bashar al-Assad, it is nonetheless important to get the development into perspective.

To put it into context, were his British equivalent – Charles Hendry – to resign, it would hardly rock the foundations of David Cameron's government. Not only is Abdo Hussameddin but a junior figure, he is also a Sunni, rather than a member of the Alawite elite which dominates the Assad regime. His change of heart is, therefore, far from the tipping point that the defection of Libya's Finance Minister proved for Colonel Gaddafi.

Meanwhile, the outlook remains altogether bleak in the rebel stronghold of Homs. The International Red Cross, and its local Red Crescent branch, are having difficulties getting supplies through to the desperate civilian population. The few remaining residents are collecting snow to obtain drinking water. Gunfire is still heard, even in the presence of the UN humanitarian aid chief, Baroness Amos. And President Assad still controls the vast bulk of both the nation's territory and its ruthless army.

There are some optimistic straws in the wind, not the least of which is that several senior figures in the military have now switched to the opposition. One armed group, claiming to be Alawites, defected on Wednesday; and there is also a gradual increase in the number of ordinary soldiers deserting to the rebels.

There are subtle shifts in the international community, too. Washington is talking of supplying the rebels with non-lethal aid and President Obama has asked the Pentagon to set out military options. China's envoy has told President Assad to stop the violence. And even Russia's President-elect, Vladimir Putin, has said he has no intention of providing asylum for the dictator if he is forced out.

But Syria's rebels are fragmented and poorly equipped. They have no tanks or artillery and their leaders are disorganised. It is a long road to the end of the Assad regime, and this week's developments are just a few tiny steps along it.