For almost every monumental cause pressed by thousands of souls protesting at our national Mall -- jobs, voting rights, equal rights, peace, citizenship, falun gong -- there has been a responding sneer.

But if enough cynics and scoffers descend on Washington next month, we'll see something new in the nation's capital: a prank of epic proportions.

Last week Jon Stewart, the host of The Daily Show, announced that he will hold the Rally to Restore Sanity, a satirical response to Glenn Beck's teary August demonstration to "restore America."

That same day, Stephen Colbert of The Colbert Report says he's going to counter with the "March to Keep Fear Alive," mocking the Al Sharpton march that countered Beck's.

In one sense, there's nothing new about lampooning protesters.

In 1894, the brigades of unemployed men who marched from Ohio to Washington to demand work, known as Coxey's Army, were written off as "performers" and "cranks."

After women marched on Washington in 1913 for the right to vote, senators lamented that making a pilgrimage could become a habit for the disenfranchised.

And during the protests against the Vietnam War, even cartoonist Gary Trudeau couldn't resist poking fun at the peace marchers, caricaturing them in "Doonesbury" as hippies with little more to say than "Hi Mom" once they got Lincoln's feet.

"There has always been some sort of mockery," said Lucy Barber, author of Marching on Washington: The Forging of an American Political Tradition, and an expert of the history of political marches on Washington.

But a mockery on a grand scale, a thousands-person-strong lampoon of Americans on the hallowed ground around the Washington Monument?

Unheard of, Barber said.

So if thousands of people actually show up for the rally making fun of a rally on the national Mall on October 30, it could be one, giant, historic snicker.