Berger was a man of the written word and back room negotiation, not a notable public speaker. He retained a heavy German accent and had a voice which did not project well. As a rule he did not accept outdoor speaking engagements and was a poor campaigner, preferring one-on-one relationships to mass oratory. Berger was, however, a newspaper editorialist "par excellence". Throughout his life he published and edited a number of different papers, including the German language "Vorwärts" ("Forward") (1892–1911), the "Social-Democratic Herald" (1901–1913), and the "Milwaukee Leader" (1911–1929).