This may not solve the crisis. Ghannouchi is not necessarily any more popular than Ben Ali, though he's not nearly as tainted by the lurid tales of corruption and excess that so damaged the ruling family. But Tunisians certainly don't respect the prime minister; they call him "Mr. Oui Oui" because he's always saying yes to Ben Ali.
It remains to be seen if the rest of the regime survives, but it seems likely that without Ben Ali as the focus of public anger the interim government might be able to quiet things down.
The “Tunisia scenario” looks remarkably like the overthrow of Bakiyev in Kyrgyzstan, and somewhat like Kyrgyzstan the Tunisian riots exploded out of a combination of resentment against corruption in the ruling family, rising prices, and authoritarian government. We can hope that Tunisia will not be wracked by the factional violence that plagued Kyrgyzstan after Bakiyev’s fall.
Elizabeth Dickinson spoke with a Tunisian opposition journalist:
"There will be a military coup -- we will see. You will see," [Taoufik] Ben Brik told me. "The army has just closed down the airspace in Tunisia, and they are arresting members of the family."
Max Boot believes "the end of Ben Ali’s long-lived and heavy-handed rule is not to be mourned, even if he was a reliable American ally":
[Today's coup] is either good news or bad news. It all depends on what comes next. If Tunisia makes the transition to democratic rule, that would be an epochal development that could influence neighboring states in a positive way. If another dictator comes to the fore, that would not be so good. Even worse would be if that dictator emerges from the Islamist fringe. Stay tuned.
(Photo: Smoke rises from fire left after clashes between security forces and demonstrators in Tunis on January 14, 2011 after Tunisian President Zine El Abidine Ben Ali's address to the nation. By Fethi Belaid/AFP/Getty Images)