At the start of January it was unthinkable. By the end of February it had started to seem unstoppable. Revolutions in Tunisia and Egypt appeared to be creating a kind of shock-wave that was rattling regimes throughout the region.
Since then of course, the process has appeared to stall.
End Quote Nacer Mehal Information ministerAlgeria is not Egypt and it's not Tunisia. We already had our process of change going all the way back to 1988”
Comparisons were made with the wave of creative destruction that swept through Eastern Europe in the early 1990s.
But they were comparisons that ignored a crucial difference: Eastern Europe was under military occupation by a super-power (the USSR) and was in thrall to a unifying ideology - communism.
Once both had gone, change became possible.
And of course the truth is - as Leo Tolstoy once wrote of unhappy families - that every Arab autocracy is autocratic in its own way.
Letting off steam To find the limits of the Arab spring I travelled to Algeria.
It was one of the countries which saw a brief flourishing of street protest in January - and it was also among those where the sparks of discontent failed to ignite into the flames of revolt.
To Algerian Information Minister Nacer Mehal the reasons for that are obvious.
"Algeria is not Egypt and it's not Tunisia," he said simply.
"We already had our process of change going all the way back to 1988. I don't believe that Algerians are frightened of this government."
"Our windows are open," he said, sniffing in a great lungful of air by way of illustration.
The personable Mr Mehal is a former journalist whose easy-going style makes him an attractive front-man for the generals in civilian suits who wield real power in Algeria.
And as you would expect his explanation for the relative stability in his country glosses over some of the grimmer realities of recent history.
The defining moment in that recent history came in 1991 when a military-backed government over-turned the results of an election on the grounds that first round results suggested that an Islamic party was heading for victory.
End Quote Protester in AlgiersOne day this will be bigger than Tahrir Square - but not today”
Even some members of the opposition will cautiously admit that the grinding years of violence have left many Algerians with a hunger for stability that might outweigh their appetite for immediate change.
No-one would call the government of President Abdelaziz Bouteflika subtle but its response to the Arab spring has been interesting.
Policing of protests of course has been heavy-handed, but it has been accompanied by measures designed to let some of the steam out of the momentum of the calls for change.
Photo warnings Subsidies can always be tweaked and salaries changed to take the edge off the economic edge to the discontent.
The official media too can be subtly changed to take account of changing times.
In a move which captures the very essence of incremental reform we were told that a planned revision of the constitution meant that certain criticisms of the president could still land you with a fine, but no longer carried the threat of imprisonment.
Journalists working for the state television service told the BBC that they enjoyed slightly greater freedom to mention opposition activity.
That might not sound like much - but in a country where photo editors get warning phone calls about not using pictures which show Mr Bouteflika's comb-over flapping in the wind, it is something.
After a week in Algeria we attended an opposition rally where we counted 32 protesters and 175 uniformed riot police backed up by a harder-to-count number of men in plain clothes.
One young protester said to me simply: "One day this will be bigger than Tahrir Square - but not today.
"We will keep returning every week though until things begin to change and Algeria has democracy."
For the moment though, that feels like a distant hope.