Why do Christians like to pretend that Hitler "invented a cult" when it was really Pr

Protestantism via it's founder Martin Luther and his book "of the Jews and their lies"

It is simple...because it was a cult.
True there were some basis in mainstream religion but the majority of the creepy stuff was not.

That's not what the word "cult" means

Exodus 20:13 Hitler was a mass murderer.
Jesus was a Jew and so were his 12 buddies. (Acts 2:14) Peter was preaching to his fellow Jews. According to Hitler's ideology, Jesus, his disciples and the entire church of the first nine chapters of the book of Acts should have been marched into a gas chamber. Some Christian!
http://bartonpaullevenson.com/Hitler.html

Because Christians hate to be reminded about the Nazis. Many Christians in America didn't mind the Nazis because they hated Jews. The Nazi soldiers had belt buckles that said in German "God is with us". Nazism was NOT mainstream Protestantism by any means, but at the time many Nazis and many Christians of that era did in fact have similar biases and similar beliefs.

My feelings as a Christian points me to my Lord and Savior as a fighter.
- Adolf Hitler

As a Christian I have no duty to allow myself to be cheated, but I have the duty to be a fighter for truth and justice... And if there is anything which could demonstrate that we are acting rightly it is the distress that daily grows. For as a Christian I have also a duty to my own people. - Adolf Hitler

The foolish-minded man, in particular, has the sacred duty, each in his own denomination, of making people stop just talking superficially of God's will, and actually fulfill God's will, and not let God's word be desecrated. For God's will gave men their form, their essence and their abilities. Anyone who destroys His work is declaring war on the Lord's creation, the divine will. - Adolf Hitler

Secular schools can never be tolerated because such schools have no religious instruction, and a general moral instruction without a religious foundation is built on air; consequently, all character training and religion must be derived from faith ...we need believing people. - Adolf Hitler

We were convinced that the people need and require this faith. We have therefore undertaken the fight against the atheistic movement, and that not merely with a few theoretical declarations; we have stamped it out. - Adolf Hitler

Hence today I believe that I am acting in accordance with the will of the Almighty Creator: by defending myself against the Jew, I am fighting for the work of the Lord. - Adolf Hitler