Yemen is a partial success at best

The Arab League's transition plan for Syria is already being compared to the GCC initiative for Yemen. When that plan was mooted last spring, the departure of President Ali Abdullah Saleh was considered the key objective to restoring stability.

Eleven months on, and with Mr Saleh having left on Sunday, it's clear that goal was just the first step.

Certainly the immunity deal offered to Mr Saleh was a bitter pill for many Yemenis. If it results in a genuine and relatively peaceful transition of power, then the immunity from immediate prosecution will be seen as worthwhile. The worst scenes of the protests - snipers shooting at civilians from rooftops, for example - will not be forgotten, but a reluctant pragmatism argues for a deal, any deal, that removes Mr Saleh from power.

That is, if Mr Saleh has really stepped down. The president (and he still is president, whether in the country or not) leaves behind an infrastructure of control that is still intact. He has announced plans to return after medical treatment in the United States, with Washington insisting that his stay would be temporary in any event. Whether Mr Saleh finds refuge in Saudi Arabia or elsewhere in the Gulf remains to be seen.

In awarding Mr Saleh amnesty from prosecution, Yemen's parliament also gave his aides protection from "politically motivated" prosecution. More than a dozen of Mr Saleh's sons, nephews and in-laws still occupy top security and political posts. Impatient for change, hundreds of air force personnel yesterday staged protests calling for the departure of Mr Saleh's half brother, General Mohammed Saleh, the head of the air force.

Beyond military divisions are tribal and ideological splits that could deepen in the absence of a genuine unity government. From the Houthi north to secessionist south, Yemen's challenges will outlive Mr Saleh's tenure in any event.

Next month's "elections" will be a rubber-stamp process that will select Mr Saleh's long-time deputy and vice president, Abed Rabbo Mansour Hadi, as the consensus candidate. Then the new question is raised whether Mr Hadi will really shepherd in change.

The GCC initiative started from the right place, to provide for a gradual transition of power with minimum bloodshed, even at the cost of Mr Saleh's immunity. But it will only be worth it if the transition does occur.