Deacon offers us what looks like a negative definition of "God":
God by definition is infinite, eternal, nonphysical... If God is, God doesn't exist. If God is, God can't exist. If God is, God isn't a fact. If God is, God isn't as things are. If God is real, God isn't real in the way that an object is.and therefore
If God is, existence discourse isn't applicable to God's isness. If God is, we need a different kind of script to talk about God.
Whether Deacon's essay really does establish something meaningful, or merely hides the nonsensical vacuity of god-talk behind some metaphysical mumbo-jumbo is better suited to the comments of Deacon's essay or the repost of my comments here.
In this post, I want to talk about the nature of atheist discourse, especially the Dawkins/Harris/Marcotte "you're wrong and we're right" that I myself espouse, and Deacon's charge that atheist discourse obtusely employs inappropriate standards, and is thus dogmatic.
Speaking from my own perspective—a lifelong more-or-less atheist (now more than less) reasonably well hooked into the atheistic philosophical community—I think Deacon misunderstands the project of political atheism.
The atheistic political project is primarily about undermining and (in the very long term) eradicating existential God belief and God talk: We want to demolish the notion that God exists—a construct Deacon himself explicitly denies (and good for him). (As a philosopher, I have an additional project in eradicating the kind of metaphysical mumbo-jumbo to which Deacon appears to be retreating (even Postmodernism and deconstruction, in my not at all humble opinion, shouldn't tolerate arrant bullshit), but that's beside the point.)
The "existential atheist" project is primarily political rather than philosophical: It is aimed not primarily at discovering the t/Truth but rather at actually changing people's minds. It is not a philosophical project not out of any unconcern with the truth, but rather because "God does not exist" is, one way or the other, blatantly obvious. The truth has been established, the task is to convince people of it.
The charge that existential atheists are addressing the "wrong" conception of God or talking about God in the "wrong" sort of language either misses the point of the project or commits a No True Scotsman fallacy. It is admittedly the case that no small few theists actually do use existential language when talking about God, and we atheists weren't the ones who started the practice.
The goal of eradicating existential theism is the same whether one goes at it from the atheist side or the non-existential theistic side. No matter how you slice it, theistic or atheistic, the notion that God exists is a delusion, and truth-seeking people of any stripe should resist and denounce the delusion. The theists have had at least five hundred years since the invention of the scientific method to clean up their act; since they haven't yet succeeded, we atheists are joining the fray.
(coming soon: Existential theism and authoritarianism)