Salam! Which is worse according to Islam: an atheist, or a mushrik?

Alaikumassalam wa rahmatullah,

They are the same thing actually. An atheist is someone who thinks there is another power other than God that is in charge of the universe, it’s just like believing in any other false god.

And I believe it is an axiom that active rejection of God = passive acceptance of Satan. Whenever someone rejects God, Satan becomes their guide, because they will no longer enjoy God’s protection from the thoughts that Satan inspires in them. This perhaps explains why so many atheists are so extremely bitter. Maybe they unknowingly reflect Satan’s bitterness.

I have of course met extremely moral and principled atheists. One of my favorite authors is Terry Pratchett, an atheist.