Who killed Gadhafi? And threw out Mubarak and Ben-Ali? Who sent Saleh into exile, and drove Assad to carry out his brutal crackdown?

No one man, of course. But, in a way, Mohamed Bouazizi was responsible for it all.

Bouazizi was a vendor in a rural Tunisian town – a man who struggled to make a living, was harassed by local police for years, frequently punished and forced to pay bribes and fines for questionable offenses. None of this distinguished him from millions of other poor workers across the Arab world. What distinguished Bouazizi was what he did next. Last December 17, furious after a female city official confiscated his vegetable cart, Mohamed Bouazizi found a gas can, walked into a busy intersection, and shouted, “How do you expect me to make a living?” Then he poured the gasoline over his head, lit a match, and set himself on fire. He died two and a half weeks later.

The rest is history. Bouazizi’s plight and story galvanized his nation – and the public anger and protests that followed drove long-time dictator Zine El Abidine Ben Ali from power. After 23 years in office, Tunisia’s dictator was gone just ten days after Bouazizi’s death. Ten days after that, a protest flared in Cairo; and by February 11, Egypt’s President Mubarak was gone. Then came Libya. Then Bahrain. Yemen and Syria. And so on.

Today there is a square in Paris called Place Mohamed Bouazizi; the main square in Tunis bears his name as well. And on Sunday, Tunisia holds elections – the first post-revolution vote since the “Arab Spring” began.