Why do they always assume the silent are in their camp?

Chris Mooney of The Intersection has a post up wondering how to rouse the great “silent majority”. You know, to oppose the evul New Atheist fringe which is RUININGZ TEH PROGRESSIVITY AGENDAZ!!!1111!!!! Apparently. Something of that nature.

my sense, too, is that the silent majority doesn’t side with either of the extremes.
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At the same time, though, let’s face it-in the science blogosphere, we don’t hear a lot from the “silent majority.” Rather, and admittedly with some important exceptions, we hear from the New Atheists.
Yet I am arguing on behalf of the silent majority,

Are you Chris? Why do these types (much like the Moral Majority folks) assume that everyone who is not ranting loudly against them is secretly on their side?