"Friend" at work blamed the Jews for WW2

Preface by saying I’m naturally a very private person so people don’t know that I’m Jewish. I was talking to a coworker when we started talking about the Hiddenburg and Bismarck. I said, “You know Hitler was such a asshole. Imagine what could have been if he’d not been a bigoted P.O.S.,” So he tells me, “Yeah, he could’ve been great, but it is important to know the Jews banded together and isolated themselves from the rest of Germany to sabotage the German economy”.

It was a punch to the gut. I wish I had said something witty or maybe tried to help him see how he was wrong. I just was silent, and I feel so guilty. My comment mainly was saying I hate that the architectural and engineering talents were wasted on an asshole who just wanted to promote a deranged and false “superrace mentality.”