Aside From The Obvious: Racism 101
Would we ever question the natural citizenship of a white person running for president? Heck some Republicans were trying to repeal that provision to help the Governator of California who is undeniably not a natural born citizen.
Did we ever call Richard Nixon socialist (when it meant something) when he imposed wage and price controls or even tried to reform health care?
Did we question the integrity of Bush 1 when he addressed the nation’s schoolchildren and asked them to write him telling how they would help him? Yes precisely the same request, but no fears of brainwashing then and no demand for releasing the text in advance.
Is it any surprise that the worst outbreaks of this hostility are coming from the old Confederacy?