Once the new immigrants had a foothold, then came the task of survival, and after that commerce, and after that, self-rule. Out of the vast spaces were carved colonies, and then states, and then countries. And still others came, to try and fill up the space, to make new lives and to breathe free. The natives could only watch as their world continued to shrink; they fought where they could, but mostly they retreated, or worse, died. They would wind up crowded into tiny, arid, inhospitable reservations, while the waves of foreign immigrants continued to pour over the land, swallowing it up.
Every group that came after were looked upon as pariahs, no-good layabouts looking for an easy buck or trying to take the jobs of the hard-working "natives." The Italians, the Irish, the Chinese, et. al. -- each group would suffer under the prejudice of those who came before them, denigrated for being late-comers who were only there to deprive "real" Americans of jobs and wealth. This did not stop their exploitation, though, for the newcomers would do anything, take any job, for any amount of pay, simply to earn a living, and would toil far harder than most to scrape out the "American dream."
This cycle repeats, a new group washing up on the shores of the glittering promise that is the land of the free and the home of the brave, to fill the cracks in American society, take over the manual and menial jobs, and fill the ranks of the more skilled positions with labor that is cheap. They face the same kind of ignorance and prejudice that all the groups that cam before them faced. They do it mainly to make money to send back home, to countries where there is little or no work, or where jobs pay so little that living is difficult. In many cases they have come here illegally, gambling that will find work and be able to avoid drawing the attention of the authorities.
There is a great amount of invective bandied about on the subject of what to do to those who are here illegally, and how to keep more from getting in. The fact is, no amount of walls and border crossings and security is going to completely shut off the flow of illegal immigrants. The borders of America are far too expansive, of too varied a terrain, to be easily patrollable or defensible. Those who want to get in, will get in; those who can make a buck helping them get in, will help them get in.
As to those who are here, their number is so great that any concerted and sustained effort to root them out will be fruitless, for even as many are removed, still more will get in. That, and those that are here have insinuated themselves into the fabric of modern American society so deeply, that for them to disappear would inconvenience so many citizens, that there would eventually be a hew and cry. These new immigrants fill positions that others do not want or think beneath them -- busboys, cooks, gardeners, landscapers, handymen, maids, housekeepers, nannies, etc. They are cheap labor, and many a "real" American is willing to look the other way to slip them a pitiable sum in cash to have their hedges trimmed and their sheets folded, even as they declare in public that "these people must go."
The solution, as with anything, is pretty simple: make them citizens. Give them the opportunity to come out of hiding. Allow them to take their rightful place in this country, to live under the protections of the Constitution, and more importantly, to pay taxes on their income. Let them pay their way to be here, and still be able to send money home to support their families. Let them come, let them live, let them add their culture and their grit and their determination to the tapestry that is the long roll of American immigration. For a nation that prides itself on its freedom and independence, what greater way to show it than to throw open the doors, let them in, and absorb them into the nation that was built by immigrants.