A mural of the rapper formerly known as Kayne West, by Jason M. Peterson, was painted over on a building along West Lake Street at South Sangamon Street. The musical artist drew backlash after making antisemitic remarks on social media and in interviews. (Erin Hooley / Chicago Tribune) Recently I’ve been startled at mulling over a question that bedeviled my Jewish forebears back to biblical times: How will I know if it’s time to leave? This question forced my great-grandmother in the first half of the 20th century to make the Sophie’s choice that novelist William Styron wrote about, one...