Mike Segar / Reuters

The Tea Party was once a joke, an aberration, a bunch of funny people in funny hats with neither power nor a coherent message. That was back in 2009, of course, before the loosely-defined group, organized through new technology and fueled by anger over the state of the country, began knocking out incumbent GOP senators and transforming American politics. Back then, Rachel Maddow laughed at the crude implications of “tea-bagging,” and White House Spokesman Robert Gibbs joked about how little the White House cared.

Today, people around the country are rallying around a new ill-defined movement, which has for now taken its name from its first act of civil disobedience: Occupy Wall Street. For now, it looks marginal, rag-tag, ill-defined and without focus. But keep an eye on it. To paraphrase Buffalo Springfield, something may be happening here.

In its broadest outlines, this new outpouring of protest is driven by the same fuel that gave fire to the Tea Party: Anger at elites, a feeling of injustice, a concern about jobs, fear about the direction of the economy and a clear desire to take action. Whereas the Tea Party focused these furies on government, Occupy Wall Street focuses the fury on corporate America. It seems, quite simply, to be the left’s answer to the right’s size-of-government critique that has dominated national politics for the last two years. “If you are like me and you see the Tea Party on the television and the news all the time, and you wonder why the hell isn’t there a radical left answer to the Tea Party, you should be here,” says one participant, in a YouTube documentary of the Wall Street event, which is worth watching.

But then, like the Tea Party, Occupy Wall Street is not about a place, but a viral idea that American democracy should be more participatory. It is everywhere, with supporting protests showing up in Boston, Chicago, Los Angeles and dozens of other cities. And there is great potential for it spreading further. If you have not already, take a look at this Tumblr account called “We are the 99 Percent.” It is a gripping, open-sourced place for people to vent their furies and frustrations about the downward trajectory of the American middle class. The blame is placed squarely on the wealthy individuals, the banks and the corporations that have largely escaped harm. Play this out. How many people, not currently involved in politics but savvy about building communities with new media, can come to a site like this and be inspired to get involved. The thing about viral efforts is they tend to explode into the national consciousness. You don’t see them coming, and then they are everywhere.

There are clear differences between the Tea Party and the Occupy protests. The Tea Party was older, whiter, more rural and, at least initially, more focused on electoral change. Where as the Tea Party inspired a huge share of regular Republican primary voters, it is not clear that the people gathered on Wall Street or in Los Angeles vote, or even see voting as a worthwhile endeavor. But there is huge potential here. It took months for the Tea Party to begin organizing with the help of professional political consultants and activist non-profits. Similarly, there are signs that the labor movement has already begun working with the people on Wall Street, and the Campaign for America’s Future, a long-time institutional force behind the traditional progressive movement, is meeting early this week to discuss ways of expanding the protests.

No one knows what will happen next, but chances are better than even that more and more Americans will be taking an active role in making it happen. That is, after all, how politics works these days. Passions build and then burst into the public sphere. Technology provides the platform to let people self-organize, and more often then not, these people are stunned by their power once then take advantage of it. Over time, this self-awareness shifts the national debate, and then starts showing up in the polls. This dynamic is what brought the Arab Spring to the world. In the United States, it happened in 2005, with the rise of MoveOn and the NetRoots, to populist efforts that supported several successful Democratic cycles. It happened again in 2009, with the rise of the Tea Party, which reshaped the Republican Party. Now it is 2011. The left has increasingly lost faith in simply following President Obama’s lead. It may be happening again.