【正确答案】 Starting in the early 17th century, immigrants have flooded into what is now USA. The population continues to become more and more diverse, with Asia and Latin America contributing millions to add to the European and African diasporas of earlier years. A nation of immigrates in fact refers to a process by which early immigrated groups privileged their own kind while looking down on later arrivals. The dominant class came either from England or adopted the values and prejudices of the English. They were anglophilic; that is, they saw themselves as following English upper-class manners and tastes.
   To track this process in the 20th century, the best place to start is with a metaphor that was adopted by large numbers of Americans as their own serf-definition of the nation. That metaphor is "the melting pot," an association with life in America that first surfaced in late in the 18th century. In the 20th century the new currency of this image dates back to 1905 when a popular play by that name was first produced by a visiting Jewish playwright from England named Israel Zangwill.
   The White Anglo-Saxon Protestants welcomed the image of the "melting pot" as self-congratulation. They didn't understand the image as implying that, in the New World, all differences would be melted away to form a radically new mixture. Instead the anglophiles presumed that any characteristics that deviated from the WASP norm would melt away. In short, they saw the melting port image as confirming their own dominance.