The biggest challenge that we have to get beyond in discussing immigration reform is the concept of “legal” and “illegal” immigration.
Throughout most of American history (until 1907) the only legal basis for immigrating to the USA was the color of your skin — and it had to be right tone as well (caucasian yet not Mediterranean or Eastern European).
So when someone says that their forbears immigrated “legally” to the USA they often are only barely technically correct. There was no restriction on immigrating to the USA prior to 1907 other than being racially qualified.
Although the 14th Amendment, passed in 1868, protects children born in the United States it was not until 1898 (United States v. Wong Kim Ark) that non-whites or non-blacks were allowed to be included under the protection of this part of the U.S. Constitution.
Prior to 1907 you only needed to buy a ship ticket or enter via some port (land or sea). No visa required. No immigration paperwork other than you checked in at the port and no reason was found to bar you.
The first naturalization law in the United States was the Naturalization Act of 1790, which restricted naturalization to “free white persons” of “good moral character” who had resided in the country for two years and had kept their current state of residence for a year.
Migrant workers were always welcome into the USA, they just weren’t eligible for citizenship. Most of our current illegal immigrants are here because U.S. industry needed them and has been willing to pay for their services. Where once we had “indentured servants” (7 years of service to an employer) we evolved long ago to employing migrant workers once indentured servitude was outlawed.
In 1870, the law was broadened to allow African Americans to be naturalized. Asian immigrants were excluded from naturalization but not from living in the United States.
It was not until 1921 that the United States Congress passed the ‘Emergency Quota Act’, which established national immigration quotas. The quotas were based on the number of foreign-born residents of each nationality who were living in the United States as of the 1910 census.