A big problem with attacking an entire group of people because of their professed religion, which is exactly what Hitler did, is proving that they all think the same, that they all agree with and support some small group that claims to somehow act in their names or on their behalf. If we're going to be relaxed about that one, then this putative future American leader person will have to throw out the Buddhists as well. You see, a bunch of Buddhist fanatics, the Ohmu Shinrikyo, attacked the subways here in Tokyo with poison gas not long after I moved here. Thousands could have been killed, including some of my friends -- imagine a packed morning rush hour Japanese subway attacked with poison gas bombs in four different locations. As it turned out less than a dozen were killed, although over a hundred people went to hospital. The trials and manhunts continue even to this day, although they've died down. It was a kind of Japanese 9/11. They had plenty of poison and they got it to the right places but I guess the deployment wasn't quite perfect so it turns out there were more United 93s than not and only a few bereaved families.
Obviously these people espoused the teachings of Buddha, as did their leader, Shoko Asahara, who was arrested shortly after. So it's a no-brainer that anybody who is a serious Buddhist believes in what they did and that it was right, right? Of course we don't want anybody who believes in Buddhism in America, since they support terrorism and would probably participate in acts of terrorism if given the chance, and since Buddhism isn't related to Christianity and Judaism, which are the founding religions of the United States of America, they can't be trusted, right?
Again, the flaw here is that the guilt of a bunch of fanatics is somehow automatically borne by an entire population who happen to be loosely associated by way of shared profession of religious belief, however distant, or ethnic group. I live in fear of the day that a bunch of fanatical redheads hijack something and I'll be tarred with the same fanatical brush, by the way.
I guess if you need to hate and oppress some group then any old excuse is good enough.