German authors observed, the United States had basic lessons to teach: because it had a long history of sexual relations between masters and slaves, it was a country, as Eduard Meyer reported in 1920, that was groaning under the weight of “an enormous mass of mongrels,”28 and it had consequently developed a large body of law on mongrelization, defining who did and did not belong to which race. Unlike American immigration and citizenship law, moreover, this law was “open”: it made no secret of its racist aims, and employed no devious pathways or subterfuges.
