Buchanan and Pierce were responsible for the Civil War. Andrew Johnson lost the peace. Harding is the worst since then a blithering idiot who was totally incompetent and presided over unprecedented corruption. Trump is a lot like Harding.
Anyone who lists Obama is just a partisan hack an ignoramus, or both.
The difficult ones are people like Wilson who did a lot of good and a lot of bad.
The worst ones for Jews were Harding and Coolidge who signed the immigration laws that doomed the Jews of Europe.