In the absence of real progress to report, news coverage of the ongoing U.N. climate summit in Copenhagen has lately begun to focus on the protestors.

Here is what we know: There are a lot of them (estimates range from 50,000 to 100,000). They've got some nifty signs and face paint (slogans include: "Planet not profit" and "There is no Planet B"). They've come from around the globe. And several hundred have been thrown in jail.

What we don't know is: What do they want?

For all the stories I've lately read about whether the protests were generally peaceful, whether the anarchists were a fringe minority, or whether jail time for anyone was warranted, I'm still a bit hazy on the larger point.

Where have all the good protestors - and message disciplinarians - gone?

Once upon a time, there was a grand tradition of protestors channeling their energies toward some clearly defined goal. I've written about this before for the Washington Monthly, so please excuse the zeal for history. But here's a quick run-down of the golden age of American protests:

The very first protest march on Washington, DC took place in the midst of an economic depression in 1894 when populist leader Joseph Coxey led an army of 500 jobless men to the Capitol steps to demand a public works program that would provide jobs for the unemployed.

Two decades later, in what must have been the first counter-inaugural protest, 28-year-old Alice Paul organized 8,000 women wearing white to march down Pennsylvania Avenue a day before Woodrow Wilson's inauguration. The women were there to lobby for women's suffrage, a demonstration that was rewarded by the passage a few years later of a constitutional amendment giving women the right to vote.

In 1941, the mere threat of a public protest was enough to force political change: When A. Philip Randolph, leader of the Brotherhood of Sleeping Car Porters, announced plans for a march on Washington, Franklin Roosevelt issued an executive order banning discrimination in defense industry and federal jobs.

And the granddaddy of all protests, the March on Washington in 1963, drew a quarter million people to the foot of the Lincoln Memorial to demand voting protections and desegregation of public spaces; shortly thereafter, Congress passed the Civil Rights Act of 1964 and the Voting Rights Act of 1965.

You get the point. In each of these cases, a specific goal was identified; people were rallied behind the cause; a plan was devised; and often, as in the case of the women's suffrage and civil rights marches, a button-up dress code was enforced. The objective was for the message to be taken seriously. Everyone was more or less on the same page, and there was a clear benchmark for success.

Fast-forward to Copenhagen. Not only are the protestors' intentions and goals scrambled, but reporters have even stopped asking about them. It's no longer expected that protestors should have much purpose beyond self-expression. Which is a shame.

If today's tens of thousands of Copenhagen protestors wanted their efforts to amount to more than color for reporters' stories, they would do well to recognize the real reason why the marches of yesteryear are still remembered. It wasn't just about the messengers showing up; it was about the message - and a clear goal.

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