Jeez, maybe you don't even need a unified message?

http://idealab.talkingpointsmemo.com/2011/10/occupy-wall-street-protesters-so-what-if-you-dont-know-what-were-fighting-for.php?ref=fpb

"Sikora added that just because the people there have different causes doesn’t mean they don’t know what they’re fighting for. 'Multiple goals doesn’t mean you don’t have a clear direction,” he said, adding: “It doesn’t mean you’re unfocused.'"

I think what's actually going on here is that the protesters DO have a unified message, but the different groups have different ways of describing or explaining it at the moment.   It's clear to me that Wall Street is a problem for the US economy, that Wall Street have been getting the kid glove treatment while the rest of the country gets the shaft.  I'd say every protester would agree with that.

So, perhaps I'd alter this a bit and say you don't need an articulation of the goal that everybody agrees to.