BERLIN (AP) — Artist Gunter Demnig carefully placed a palm-sized Holocaust memorial brass plaque into the sidewalk on a busy street corner of Berlin. It said: “Johanna Berger, born in 1893, lived here; deported on Nov. 17, 1941, murdered on Nov. 25, 1941.” After Demnig had swiped the sand off Berger’s memorial stone and those for her husband and two sons, a dozen relatives drew closer around the four plaques, which are called Stolpersteine, or “stumbling blocks,” in German. They put down white roses and recited the Kaddish, the Jewish prayer for the dead, while traffic roared by on a...