What would happen if someone like Hitler would adopt anti-theist ideals?

for dang certain someone needing 5 cent justice (1 bullet, 5 cents)

hitler was an outspoken atheist and adhered firmly to evolutionary thinking (which condoned the holocaust)

What specifically are “anti-theist ideals”?

You'll have to elaborate - I'm not gonna assume that you are accusing atheists of being everything from baby-killers and cannibals to psychopaths.

I'm not going to assume you're that so whacked out and totally ignorant of what an atheist is.

I'm not going to assume you don't know that all an atheist is, is one who has no belief in invisible sky gods, Ghosties, bogeymen, Santa and all other mythical and imaginary beings theists believe in.

Oh, by the way, Hitler was a brought up as a Catholic - it's where he learned his anti-Semitism.

The Führer is deeply religious, though completely anti-Christian; he views Christianity as a symptom of decay. Rightly so. It is a branch of the Jewish race. (Joseph Goebbels’ diary, 28-12-1939)

Stephen Roberts: I contend that we are both atheists. I just believe in one fewer god than you do. When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours.

The Theists wouldn't blindly follow.

What Hitler did spoke for itself, religion, or NOT!!!

Umm, Hitler killed Jews so how much more anti-theist can you get?

he did and everything that did happened. he was an occultist.