There weren't a lot of them, but for the record, yes, there *were* Jewish segregationists and white supremacists in the civil rights era.
For instance, here's a piece Clive Webb did on Charles Bloch, a leader in Georgia's version of the Citizens Council: https://www.jstor.org/stable/40584146?seq=1#metadata_info_tab_contents …
Likewise, as David Chappell noted in this piece, Robert Patterson of the Mississippi-based Citizens Council noted that they had Jewish members in their group as well: https://www.jstor.org/stable/pdf/40583696.pdf?ab_segments=0%2Fdefault-2%2Fcontrol&refreqid=search%3Aa4195dd17e982f68ced29291a79b2eaa …
Now, these figures were certainly not representative of how southern Jews took sides in the civil rights era. To be sure, many more sided with civil rights activists.
But they show that it *was* actually possible for individual Jews to make common cause with white supremacists.
You can follow @KevinMKruse.