BERLIN — As Irmela Mensah-Schramm descended from the train in Buch, a combustive locality in the north of Berlin that is a fault line in the refugee crisis, her agitation was visible. The last time the 70-year-old with snow-white hair was there, a local neo-Nazi shoved her roughly. Now, she says, she will not even venture into town, for fear that someone will recognize her and alert the thug.
Not to worry, though; there was plenty for this retired teacher to do at the station. In a passageway, half a dozen innocuous-looking green and white stickers featured, upon closer inspection, the sword-and-hammer symbol of a virulent neo-Nazi group. During lulls in foot traffic, Ms. Mensah-Schramm, who is well- known in Germany for her dogged campaign to remove neo-Nazi messages from public places, quickly went to work with a scraper.
While shakily clambering under a hand rail, Ms. Mensah-Schramm tore down a neo-Nazi …