Adolfo Kaminsky, a former member of the French resistance during the second World War, forged identity documents. Photograph: Joel Saget/AFP/Getty Images Adolfo Kaminsky’s talent was as banal as could be: he knew how to remove supposedly indelible blue ink from paper. But it was a skill that helped save the lives of thousands of Jewish people in France during the second World War. He had learned how to remove such stains as a teenager working for a clothes dyer and dry cleaner in his Normandy town. When he joined the anti-Nazi resistance at 18 years old, his expertise enabled him...