Obviously, this is a large movement with many constituencies. But it seems clear that core concerns include growing income inequality, an increasingly unstable financial sector, and a political system that has allowed both trends to continue. This is not just a protest against capitalism, although for some it is that. It is a protest against recent changes in our political and economic system, changes that have dramatically tilted the playing field. Ivy McDaniel has culled useful graphs and tables from a few sources and compiled them into a very helpful presentation that gives a good sense of the core issues. At the end of that presentation is a timeline that she wrote.

A frequent criticism of OWS is that it is incoherent. Media coverage has focused on the drum circles, the pageantry, and the more colorful protesters, often ignoring the substantive claims of movement. And when the messages of OWS are given attention, the healthy diversity of positions can sometimes be mistaken for incoherence. Remember, no political coalition is ever entirely singing off the same sheet (imagine trying to extract a core demand from the Republican party, with its odd amalgamation of evangelical Christianity, libertarian economic policy, and defense of corporate privilege). That said, there are a few demands that capture the main thrust of the movement, in my opinion.

1. Re-regulation of the financial sector. A major cause of the financial crisis was that banks were allowed to make investments that they had previously been forbidden from making, and existing regulations were not enforced. But banks are like cars. When there are no rules for the road, they crash. 
2. Removing money from politics. One reason that politicians have declined to regulate our economy is that large corporations finance electoral campaigns, and their ability to do so has grown considerably with the Citizens United decision. One desirable outcome of the OWS movement would be a constitutional amendment clarifying that corporate speech is not protected under the First Amendment or one forcing the public financing of federal elections.
   
3. A fairer tax burden. The amount of wealth and income controlled by the super-rich has been growing considerably in the last forty years. Meanwhile, the proportion of their income that the super-rich have been obliged to pay in taxes has been steadily declining. The combined effect of these is that our country has grown more unequal and less able to pay for anything. The way to fix the deficit is to tax people, as other countries do.
   
4. A social safety net. Our government has done a good job directing public funds toward protecting the banks from the effects of the economic crisis. It has done less of a good job using those funds to protect workers, homeowners, and students. If we are going to continue to have a volatile economy, we need to protect those who are hurt by it.
   

These demands, you may notice, are modest. They ask mainly for a return to the economic policies of the 1950s and 1960s. Some OWS protesters, of course, are seeking much more, from cuts in military spending and pay raises for teachers to confiscatory taxation for those making over a certain income and the closure of the Federal Reserve (which I think is a terrible idea). But this list of demands above encompasses the area of overlap for nearly all of the protesters. And it's a pretty good start.

Aren't there other ways to effect change? What good does sleeping in the park, waving signs, and yelling do?

Occupying parks is only a start. Step one involves drawing the nation's attention to economic issues and building a movement around them. That begins with marches, signs, and conversations. The next steps will require organizing, building long-term institutions, and turning an inchoate movement into effective political action. But the importance of step one should not be dismissed. Social movements can achieve powerful gains--think of the civil rights movement or the attempts to legalize gay marriage. And they are especially necessary at a time when normal political channels are blocked.

It is undeniable that our politicians, Democrats as well as Republicans, have worked for decades to create this system whereby the richest members of our society pay surprisingly little in taxes and experience few constraints on their actions. It is also hard to deny that this has had a lot to do with the increasing reliance of politicians on private donations to finance their campaigns.

But remember why politicians want money in the first place: to win elections. That means that politicians are still extraordinarily careful when it comes to issues that can gain or lose them votes. The standing bargain is that candidates facing election will pander to voters on the the public issues that everyone follows and cares about (abortion, guns, health care, immigration) and will pander to their backers on issues that voters don't understand or don't care about. The more confusing or hidden from public view an issue is, the more likely it is that politicians will represent their financial rather than their electoral base. Unfortunately, a lot of the rollback of economic regulation, introduction of various loopholes, and trimming of taxes on the richest one percent has taken the form of complicated legislation that few voters understand or follow.

Occupy Wall Street puts politicians on notice: we are watching. If you continue to tilt the playing field in favor of the rich, we are going to call you out. If, on the other hand, you introduce or back substantive legislation that responds to our demands, you will have an active, energized base upon which to draw--a base that has shown itself to be capable of putting hundreds of thousands of people in the streets.

The most important thing right now is to increase the visibility of Occupy Wall Street and its sibling movements. So visit the parks, put up signs, wear buttons, write "We are the 99%" on your money, talk to people, join one of the many actions taking place online and in your city, sign petitions, write articles, and so forth.

One thing that is particularly important is for people who do not fit the standard model of a protester to get visibly involved. That means teachers, lawyers, professors, businesspeople, professionals, and so forth. The media is drawn to drummers with body paint screaming half-baked ideas at the top of their lungs and antagonizing the police. We cannot let that be the whole of this movement. So put on some business clothes, put your kids in a stroller, make a sign, and get down there--in between the cameras and the crazy--and help broaden this movement.