The United States saw waves of immigration and several changes in immigration law from the mid-1860s to the late 20th century. Discuss the impact immigration, immigration laws, and the backlash to immigration had on the social and economic development of the United States.

The United States really had no immigration law until 1882, when Congress passed the Chinese Exclusion Act. This was a response to racialized fears that the United States, and especially the West, was being "invaded" by non-whites who posed a threat to "American" culture. The Chinese were a sort of special case, however, as immigration laws generally allowed the unlimited influx of millions of immigrants from Eastern Europe in the late nineteenth and early twentieth centuries. This massive influx of Americans permanently changed the cultural and physical landscapes of Northern cities in particular and was one of the most important contributing factors to American industrial expansion during the period. However, this massive influx of "new immigrants" brought about a nativist backlash that led Congress to pass restrictive quotas in the 1920s specifically targeted at limiting immigration from non-Northern European countries. In 1965, these quotas were abandoned in favor of a system that favored family-based immigration, and made no distinction as to national origins. In the late twentieth and early twenty-first centuries, waves of immigrants from central America in particular was met with a backlash from many Americans who rehashed old arguments about the threat immigrants posed to "American" culture. Fears of immigrant influence continues to be a major theme in American politics.
https://www.migrationpolicy.org/research/timeline-1790