Most of what is written by Melissa Barton in her ill-conceived essay is pure rhetorical garbage. It's the same sort of muddled mess perpetuated on many rightwing religious sites. She takes several extreme claims about atheism, fails to give even one credible example to back any of said claims and then advocates essentially silencing anyone that doesn't believe in a "supreme being" as she does. Fortunately, I doubt she's the arbiter of such decisions for the progressive movement.
Personally, I don't begrudge Ms. Barton her opinions; if she really has a major bone of contention with atheism, so be it. She's certainly not alone in this country. As I've written before, being an atheist makes one a member of a demographic that political correctness has passed right on by. We're routinely considered immoral or unethical, we're often either compared to or forced to answer for the actions of Stalin or Hitler, among other indignities. Again, I say, so be it. Anyone ignorant enough to confuse atheism or worse, secularism, as Barton does, with the disregard for human decency displayed by fascism has nothing of value to add to the discussion.
Atheism is not secularism, which Barton no doubt knows. Atheism can be defined in many ways, though I tend to use a couple of questions posed by noted evangelical Ravi Zacharias to aid my definition. The questions are:
Does God exist? And, if so, what is the nature of God?
I answer the second question first, which leads me to my atheistic beliefs. It's not possible, in mankind's current state of advancement at least, to know anything about the nature of God. We cannot see, taste, touch, smell, hear or mathematically calculate anything about God (or anything supernatural). Given an absolute dearth of evidence for God, either He doesn't exist or his existence is a separate notion to every single human that has ever lived. Either way, the first question becomes moot. Does God exist? We cannot know, because we cannot know anything about the nature of God.
Now, I have many friends and family who are evangelical Christians who will say "But of course we know God; the Bible tells us all about Him". No, it doesn't. It tells us all about the faith of those writing the Bible. There is no objective truth to be gleaned about the nature of God from the Bible. Only the hopes, dreams, faith and, sometimes, fevered rantings of those who authored the few Christian writings contained in the Bible. It is only proof that a collection of ancient men and women had various views on the supernatural and with some extremely tortured contextual acrobatics their beliefs can be loosely formed into a semi-coherent dogma. This is not to insult those faiths, though I recognize that many Christians, particularly the conservative variety, take offense to any questioning of their scripture. I have no problem with those who feel that the Bible is the absolute Word of God, so long as they respect my right to consider them to be engaging in a whole lot of wishful thinking. To my mind, slavish devotion to any written word as absolute truth is an abdication of the free will inherent in all human beings, be it merely human perception or a gift from the divine. I see no reason why faith needs a book to give it voice, except as an attempt to make faith an institution.
To conclude, atheism is, in my life, the realization that any perception of the supernatural is confined exclusively to the mind of the perceiver. In my perception, the universe is complete, my existence is complete, without the need for any divine source or purpose. It's tremendously liberating to me that I can believe as I choose, unconstrained by the teachings of some ancient writers in the Middle East. Maybe they're right, and certainly many of their teachings on morality are sound. But whether they are right or wrong is their burden to bear, not mine. My life changes not one whit either way.
And a final word to Ms. Barton: I don't think I'm going to let you drum me out of the progressive movement today. You're welcome to your faith, so long as you recognize that I, and others who believe as I do, neither want nor require the same spirituality that you do. We are all fighting the same battle, and we lose much ground when we turn on each other.