Illegal immigration is the major international economic issue facing the United States. An idiotic initiative towards protection might well change this, but our trade problems are of our own making. Illegal immigration thrusts itself upon us, like it or not. The topic deserves formal treatment by economists, and this paper sketches out early steps toward that end. From 1820 to 1930, the United States received about 60% of the world's immigrants. Population expansion in developed areas of the world, improved methods of transportation, and U.S. desire to populate available space were all factors in this phenomenon. Through the 19th cent., the United States was in the midst of agricultural, then industrial, expansion.
The first permanent quota law was passed in 1924; it also provided for a national origins plan to be put into effect in 1929. In 1952, the Immigration and Nationality Act (the McCarran-Walter Act) was passed; while abolishing race as an overall barrier to immigration, it kept particular forms of national bias. The act was amended in 1965, abolishing the national origins quota. Despite overall limits, immigration to the United States has burgeoned since 1965, and the 1980s saw the highest level of new immigrants since the first decade of the 20th cent.
In 1986, Congress passed legislation that sought to limit the numbers of undocumented or illegal aliens living in America, imposing stiff fines on employers who hired them and giving legal status to a number of aliens who had already lived in the United States for some time. The Immigration Act of 1990 raised the total quota for immigrants and reorganized the preference system for entrance. The 1996 Illegal Immigration and Reform Responsibility Act led to massive deportations of illegal immigrants; its provisions were later softened under political and legal attack.