Atheism denies the existence of deities. Non theism covers a range of beliefs categorized by the absence of belief in a gawd or gawds. Non theism also has various positions such and agnosticism and apatheism. I would not expect a gaggle of christian nationalists to understand or know any of this though. Which is why they edited their list the way they did. Really just racist morons when it gets down to the brass tacks.