“The U.S. and the Holocaust,” the newest huge PBS documentary from Ken Burns, is a distinct form of movie for him in that — not like “Baseball” or “Jazz” or “Benjamin Franklin” — it appears very a lot a response to present occasions, made not simply as a commemoration however as a warning. American nativism, xenophobia and white supremacy, having been given cowl by the earlier president, are renascent; the Anti-Defamation League discovered a 61% enhance in assaults on Jewish establishments from 2020 to 2021. Burns (with co-directors Lynn Novick and Sarah Botstein) will make that time specific on the...