Will a clever name, like Arab Spring or Occupy, link the protests erupting in disparate parts of the globe?  Will 2013 become a sign uniting all of them in memory, just like 1848, 1968, and 1989?

The spread of wildly different movements in very different places makes us wonder about why and how.  People live with grievances and disappointments all the time, only occasionally taking to the streets in dramatic action to try to get what they want.  What makes the protest switch flick on?

Hundreds of thousands of people, most of them young, have taken to the streets of all of Brazil’s major cities in recent days.  The protests started in Sao Paolo, explicitly focused on a relatively small hike in transit fares, but clearly demonstrators saw much more at stake.  Protesters are mad about the poor quality of public facilities, mad about corruption, and mad about massive spending on soccer stadiums to prepare to host the World Cup.  They were angry that President Dilma Rousseff seems to retain sufficient popularity to win reelection next year, in spite of their frustrations–and that there are no apparent channels to influence government that seem meaningful. And once the demonstrations started, the vast majority of them peaceful, they were angry about aggressive policing that included tear gas and rubber bullets.

More than a few demonstrators said they took inspiration from the Turkish demonstrators in Istanbul’s Taksim Square (“standing man” at left), who have been challenging the government of long-standing prime minister Recep Tayyip Erdoğan.

On the surface, the demands and the contexts seem very different. Demonstrators in Turkey are worried about protecting the secular identity of their Muslim democracy.  Among the litany of complaints in Brazil, incipient theocracy is not one.

But people take inspiration from the very existence of others trying to take action to make their governments more responsive and to better their lives.  Remember, the Occupy demonstrators in Zuccotti Park cited the Egyptian crowds in Tahrir Square as inspiration, even as none of the Occupiers was waiting for the military to take sides and escort a president out of office.  A protest song is a sing-a-long.  And even though the lyrics may be quite different, the tune feels the same, even a little familiar.

By the way, some demonstrators wore the Guy Fawkes mask popularized by Anonymous and Occupy.  When people pick up such symbols of revolt, they invest them with new meanings, their meanings.

When the sufficient tinder is dry, any spark can start a fire.