“This is a bird's-eye view of the substance with which Americanization deals. The burden of Americanization to-day lies as much among the various races as between the native-born and any given race. It is often easier for native- and foreign-born to fuse than it is for diverse races, and the native-born is often an indispensable element of fusion among the newcomers. Americanization is also essentially a problem of men, since the women of old races in America still follow the leadership of their men.”