I've talked about jewish responsibility for communism before. The problem is complex. Dissecting Leftism has a post that's somewhat on point. It shows how taking collective responsibility can go overboard and lead to horrible consequences. Whatever the truth about jews dominating the marxist movements of Hitler's young adult years, the jewish community's responsibility should never have gone beyond stern words of verbal disapproval and dissociation from people who personally refused to take up their responsibilities.
Hitler saw a horribly violent evil spreading throughout Germany via marxism. He made the fundamental mistake of fighting evil with evil but the error was in his evil means, not the idea of fighting an evil itself.