Leading article: Popular rage that could light fires across a whole region

It must be some cause for relief that the revolution – and make no mistake, it was a revolution – that has taken place in Tunisia was not more protracted than it was, nor more costly in civilian lives. To be sure, the confrontations were violent while they lasted, with the authorities, initially, giving no quarter.

There was extensive trashing and looting by demonstrators. But the decision of President Zine El Abidine Ben Ali to flee the country had the effect, at least temporarily, of defusing the protests, while promises of an interim national unity government and early elections hold out the chance of a breathing space in which a more durable calm could be restored and plans laid for reform.

If this is how the situation actually develops, then Tunisians will be able to congratulate themselves on an – almost – bloodless revolution and in pioneering long-overdue democratic change in North Africa. Unfortunately, there is little certainty that this is what will happen. President Ben Ali's long and increasingly corrupt rule built up frustrations that may well take more than his eviction and election promises given by temporary successors to dispel. Confusion reigned late yesterday, with speculation, finally confirmed, about the arrest of the deposed president's head of security and reports of gun-battles near the headquarters of the ruling party. For all the initial rejoicing, this is a conflict that would seem not to be over yet.

Even if it is, there is little clarity about the intentions of those who now appear to be in charge. Is the promise of elections real, or a ruse that will simply presage a new crackdown, as new leaders try to consolidate their power? If elections take place, will they be worthy of the name – and will the patience of Tunisia's opposition hold out that long? What role is the army playing?

Tunisia has long been a volatile mix. Worsening corruption, increasing unemployment and escalating food prices all contributed sparks to the conflagration that flared up last week. There are also the accumulated effects of deregulation – of which Tunisia had been regarded as a model in the region – sharp disparities between rich and poor, and the liabilities of a disproportionately youthful population. More than half of all Tunisians are under 25.

While highly symbolic, the departure of President Ben Ali alone will be nothing like enough to assuage popular discontent. If the interim authorities can keep order, while moving fast to honour the promises they have made, and if they are serious about democracy and social reform, Tunisia could emerge a better country. But these are a lot of ifs.

Nor do the uncertainties relate only to Tunisia. It might be one of the smallest countries in the Maghreb in terms of area and population, but the spirit of revolt that erupted there last week has the potential to spread across North Africa and beyond. Almost every country in the region is beset by the same ills: a corrupt and repressive – or unresponsive – government, sharp social and economic divides, high food-price inflation, and a large population that is young and underemployed. There is also, of course, militant Islam, but in this context it appears more like an effect than a cause.

It would be premature to conclude that change is finally on the march in North Africa or that – even if it is – it will necessarily, in the short term, be for the better. Things could get a great deal worse, in terms of violence, disorder, repression and military crackdowns, before they improve. And the proximity of the perennially unstable Middle East, war-torn Iraq, and an Iran whose regime was recently shaken by election protests, hardly makes for a neighbourhood conducive to calm. As the Western world looks on, it will need to keep a very strong nerve.