With a population of 16,373,645 at the turn of the 21st century, the Los Angeles metropolitan area was second only to the New York metropolitan area in size. It was the primary destination in the United States for the increasingly large immigration of Latin Americans and Asians that developed under provisions of the Immigration and Nationality Act of 1965. Of metropolitan areas with populations over 5 million in 2000, it had the highest percentage of foreign- born inhabitants at 29.6 percent. By the time the United States acquired California following the U.S.-Mexican War (1846–1848), Nuestra Señora la Reina de los Ángeles de Porciuncula had been a Mexican city for almost 30 years and a Spanish town for almost a half-century before that. Apart from the native Mexican population that stayed on, Los Angeles historically contained relatively few foreign-born citizens. Between 1850 and 1920, the percentage of Mexican Americans living in Los Angeles declined dramatically, from a vast majority to less than 20 percent. As the city’s general population boomed between 1920 and 1970 (576,673 to 2.8 million), the foreign-born population remained relatively constant, around 20 percent. Unlike most eastern urban areas, population growth in Los Angeles was principally the result of internal migration, rather than foreign immigration. Most migrants were midwestern Protestant Anglos, who eventually dominated Los Angeles politics and economic development, and most identified themselves by previous state of residence rather than ethnic background. Depression-era Anglo refugees from the dust bowl (principally the lower Great Plains) were prepared to fill menial jobs, thus limiting the need for immigrant labor. By 1970, the foreign-born population dipped to 15 percent. That downward trend was rapidly reversed after implementation of the 1965 Immigration and Nationality Act, which abolished national quotas and favored family unification in selecting immigrants. As a result of the new legislation, Los Angeles became the center of migration for many Latino (see Hispanic and related terms) and Asian immigrant groups. As Los Angeles–area industry and agriculture grew, employers lobbied for increased immigration, particularly from Mexico. Wartime demands for labor during World War I (1914–18) led Congress to exempt Mexicans as temporary workers from otherwise restrictive immigrant legislation. As a result, almost 80,000 were admitted between creation of a “temporary” farmworker program in 1917 and its termination in 1922. Fewer than half of the workers returned to Mexico, and many of them stayed in southern California. Linking with networks that organized and transported Mexican laborers, workers continued to enter the United States throughout the 1920s, with 459,000 officially recorded. Although there were no official limits on immigration from the Western Hemisphere, many Mexicans chose to bypass the official process that, since 1917, had included a literacy test, making the actual number of Mexican immigrants much higher. Most worked in agriculture in either Texas or California. The Bracero Program brought an additional 5 million Mexican laborers between 1942 and 1964. During the 1960s and 1970s, Mexican Americans made significant gains in both political representation and economic conditions; meanwhile, Los Angeles became more segregated as non-Hispanic whites fled to the suburbs. The foreign-born Los Angeles population from Mexico rose sixfold between 1970 and 1990 (283,900 to 1.7 million). By 2000, more than 5 million Mexican Americans lived in Los Angeles, making them the largest immigrant group by far. Migration from El Salvador (see Salvadoran immigration) and Guatemala (see Guatemalan immigration) rose at even more dramatic rates: The Salvadoran population rose from 4,800 in 1970 to 231,605 in 2000, and the Guatemalan, from 3,500 to 133,136. By 2000, Latinos composed more than 40 percent of the population of the Los Angeles metropolitan area. Asians were among the first immigrants to Los Angeles. By 1890, there were more than 4,000 Chinese living there (see Chinese immigration). After the Chinese Exclusion Act (1882), the largely bachelor population declined, but the Chinese population grew rapidly after 1970. In 1970, there were about 56,000 Chinese in Los Angeles; in 2000, they numbered 472,637. Throughout most of the period between 1900 and 1970, the Japanese were the largest Asian group in Los Angeles (see Japanese immigration). With their own economy very strong after 1970, however, they did not come in large numbers during the late 20th century. As a result, the Japanese population grew more slowly, from about 120,000 in 1970 to 203,170 in 2000, when they were the fifth-largest Asian group, behind the Chinese, Filipinos (438,013), Koreans (273,191), and Vietnamese (252,278). The Asians have been called the “model minorities” because of their high levels of education, work ethic, and general social and economic success. While the Chinese, Filipinos (see Filipino immigration), and Japanese tended to be highly assimilated and spread throughout the city in most areas of work, Koreans are especially known for starting small businesses, with whole families often working together (see Korean immigration). The Vietnamese were somewhat less successful, mainly because they were more recent arrivals, almost all coming after 1975, and, as refugees, were able to survive in less skilled areas of work with significant support from the government (see Vietnamese immigration). In 2000, more than 10 percent of the Los Angeles metropolitan population was Asian. Given its diverse ethnic background, it is not surprising that Los Angeles suffered a number of prominent ethnic clashes, including the Chinese Massacre of 1871, which saw 20 Chinese murdered by a white mob; the Zoot Suit riots of 1943, in which young Chicanos were attacked by Anglo mobs; and the Los Angeles riot of 1992 in which Korean businesses, among others, were targeted following the controversial acquittal of four white police officers in the beating of Rodney King, an African American. Growing concern about the cost of providing assistance to illegal immigrants and fear of an increased flow from Mexico as a result of the economic crisis led Californians to approve (59 percent to 41 percent) Proposition 187, which denied education, welfare benefits, and nonemergency health care to illegal immigrants. Decisions by federal judges in both 1995 and 1998, however, upheld previous decisions regarding the unconstitutionality of the proposition’s provisions. The anti-immigrant mood in Los Angeles remained strong, however, into the first decade of the 21st century. This was reflected in the massive campaign to recall California governor Gray Davis in 2003. Based in part on opposition to Davis’s support for providing illegal aliens with driver’s licences, Los Angeles immigrant and Hollywood movie star Arnold Schwarzenegger won a convincing victory in the recall election in October.