Revisiting your comment after a productive back-and-forth with Perplexed:

I realize immediately that I never addressed the substance of your claim: that, so far as I can tell, being that it takes as much faith to believe that no gods exist as to believe that (at least?) one god does. Or, to avoid the possible misuse of the word "faith", to say that any standard by which "I believe in God" needs justification is a standard by which "I believe there is no God" needs justification.

Which is perfectly correct. But it misses a lot of what is being said, for two reasons.

First, as I alluded to previously, a large contingent of affirmative atheists these days lack belief in any general god rather than assert a blanket nonexistence. There are exceptions - Perplexed is one - but it is an oversimplification to say that "atheism" is a matter of positive belief. If you go on random.org and generate an integer from 1 to 100, I will not believe that it is 42 - but I will not believe that it is not 42. I have no reason to hold any positive belief in such a case.

Second, however, we do have evidence. If you generate a number from 1 to 100, I will believe that it isn't "blue". Again, exceptions like Perplexed [edit: if Perplexed is an exception] may appear, but many of the ostensible atheists you will meet will have reasons for thinking that many or most possible deities are not real - reasons like absence of evidence and lack of support for ontologically basic mental entities. In fact, many of the ostensible theists will have reasons for thinking that one or more deities in particular are real!

What I'm saying is: it is not "as much a matter of belief", it is a factual dispute. Either the god is real or the god is not, and we have different expectations each way. To compare the two positions is a first step, but it is a mistake to halt before comparing their respective support.

In the current freethinker discourse, agnosticism and atheism are considered to be independent properties - "gnostic" meaning "believing knowledge is possible" and "agnostic" meaning "believing knowledge is impossible". There was a very active agnostic theist poster on the forum then known as the Internet Infidels Discussion Board when I was a regular, for example.

Even if this were not true, changing the definition of the word "atheism" merely means that the word no longer describes the people you are disagreeing with - not that their opinions must correspond to the new word.

(If you are a YouTube fan, QualiaSoup's "Lack of belief in gods" is a pretty good overview.)

And bald is a hair color.

I'd say it's because all current atheist writers are human, and therefore suffer from the same basic limitations of brain design as theists. A rational AI could, in principle, form and communicate beliefs without being as vulnerable to the trap.

But you probably meant that atheism and theism are both non-fact-based, which is a bigger inferential gap than I'm willing to try to cross right now. (Edit: And I don't get how it's implied by the existence of a middle ground at all.)