Please don't take this the wrong way. I wouldn't say anyone is a racist or antisemite if you can't give strong evidence for it. I've been called an antisemite many times on Medium and they took down one of my stories so I'm a bit sensitive to this issue.
Yes, Patton definitely said racist things. I don't need to read letters for that. But not in a way I think it fair to call him a racist. Also, antisemitism back then wouldn't have meant the same to that generation. It's a new word. I go into that, in one of my stories I believe. To his generation, and to Shakespeare, Jews were not poor Jews who ended up in extermination camps, it was the rich and powerful. Of course, there was antisemitism towards ALL Jews, but generally, someone like Patton wouldn't mean it that way. It's a complex subject. So I believe one has to be extra careful it calling someone from previous generations anti-anything because context is important.
Thanks for understanding!