The 1965 act marked a radical break from the immigration policies of the past. The law as it stood then excluded Latin Americans, Asians, and Africans and preferred Europeans. In order to convince the American populace - the majority of whom were opposed to the act- its proponents (Ted Kennedy, Johnson...) assured that passage would not influence America's culture significantly.
Immigration changed America's demographics, opening the doors to immigrants from Asia, Africa, and the Middle East. The number of Latin American immigrants also dramatically increased after 1965, though this was more due to soaring population in Latin America and the Caribbean. It is worth noting that this act introduced immigration quotas from Latin American countries, whereas there were previously no immigration quotas from the Western Hemisphere (also see National Origins Formula). By the 1990s, America's population growth was more than one-third driven by legal immigration and substantially augmented by illegal immigration, primarily from Latin America and other parts of the developing world. Before passage of the Hart-Celler Act, immigration accounted for only ten percent of population increase in the U.S. Ethnic and racial minorities, as defined by the US Census Bureau, rose from 25 percent of the US population during the year 1990 to 30 percent in the year 2000 and to 36.6 percent as measured by the results from the 2010 census. Similarly, during the same time period the non-Hispanic white population in the United States decreased from 75 percent of the overall US population in 1990 to 70 percent in 2000 and finally to 63.4 percent during the year 2011. It is estimated that by the year 2042, white people not referring to themselves as Hispanic will no longer constitute a majority but rather only a plurality of the population of the United States. Non-white groups, led by Hispanic Americans (mainly Mexican Americans), Black Americans, Asian Americans, Native Americans, and Pacific Islander Americans would together outnumber non-Hispanic White Americans. According to the 2000 census, roughly 11.1 percent of the American population was foreign-born, a major increase from the low of 4.7 percent in 1970. A third of the foreign-born were from Latin America and a fourth from Asia. The passage of the Hart-Celler Act contributed to increased illegal immigration from Latin America, especially Mexico, since the unlimited legal bracero program previously in place was eliminated.
Let it be said that despite encountering problems such as importing disease, not finding employment possibly due to discrimination, and not assimilating easily, there are also may success stories. For instance, an illegal that I know, has 3 "kids" who have been nationalized and are achieving the American dream. One is studying medicine, another is a mortgage banker, and the third is management in a service industry.
At this point the floodgates have been opened & any discussion for a "solution" borders (hahaha) on lip flapping. IMHO.