Protests are increasingly powerful tools for change. From the WTO protests in Seattle, to Genoa, to recent antiwar protests and the actions in Cancun that helped shut down the latest round of global trade talks, global democratic forces have gotten smarter and smarter, more and more effective.

How do they do it? The answer is complicated, but the short version is, they swarm. Well-trained in civil disobedience, linked by cellphones, email and online maps, operating in affinity groups and clusters, backed by ad hoc teams of independent journalists, neutral observers and lawyers, protesters can ebb and flow across an urban landscape with a speed and coherence that leaves security forces scratching their heads, looking befuddled. As it stands now, there is no city on Earth that can't be shut down by 10,000 serious, swarming protesters. Anywhere cellphones will work and airlines fly, activists own the streets.

It's not that police aren't trying to fight back. While the stories of Geneva police shutting down the cellphone network to stiffle protests during the G-8 meetings there have turned out to be apocryphal, it's clear that the police now understand perfectly well what a swarming protest is. But so far, every effort of the riot cops to meet swarming tactics with new counter-tactics has found itself overmatched by the power of a distributed but well-connected group of people to innovate on the fly, especially since in an age of ubiquitous media, police violence merely gives protesters a propaganda coup.