America is moving toward theocracy, so should atheists or agnostics care?
You have made a fine example of a slippery slope fallacy. We aren't anything like a theocracy.
Yeah, it's fallacy now for sure. Later, who knows?
And, it all depends on how one defines theocracy. Some folks claim we're there now. That's a stretch. Nonetheless, there's plenty of ambiguity in the constitution, so things can drift that way to a significant extent.
Gorsuch is a significant slip down the slope. Once Bader-Ginsberg goes, things can go into high gear. Trump's judicial nominees are all rather hard core Christians. The nest few years will be interesting. If Trump gets 3 supreme court picks, things will be really interesting. And, there is prospect of a state-called constitutional convention looming in the weeds. That could be a real game-changer, although odds are still against it.
I think you should read the definition of theocracy...and there's no danger of America becoming one. That sounds more like anti-Trump sentiment and fear mongering. The U.S. is a free country with a Constitution that may as well be written in stone.