Ethnicity in the United States has historically been problematic and remains controversial. At the turn of the twenty-first century there is no public agreement about immigration policy or how immigrants can best learn English. There is no general agreement on the role of ethnic food, delicious as it may be, in American culture, nor is there an accepted academic theory about how it evolves. Some phenomena, however, seem to repeat themselves over the centuries and across ethnic groups. The patterns in ethnic cuisine were first described in the so-called new immigration period of 1880–1924 but generally correspond to what is known about earlier immigrants, and can be observed—with help from the news media—among later immigrant groups. The apparent exceptions to these patterns are ethnic groups of color whose intermittent segregation and progress have produced either cultural conservatism (Chinese and Japanese Americans) or complex layers of meaningful foods (African Americans, Native Americans, and Mexican Americans).