The reason this is relevant is because it radically reshapes migration. It means that each and every person who came to this country managed to contribute to society and start earning a living, or they left. As a result of this each and every migrant was, at worst, a non-negative on society. They integrated, they contributed, and society was all the better for it.
Today society is much more humane, and that is probably a good thing. But it also means that each and every person who lives, or comes, to within this country can now be a net negative on society. And so this rather radically changes the calculus. It means each and every person who comes to this nation, if incapable of providing for themselves, stretches our society's finite resources that much thinner. Consequently, there is need for judiciousness and restraint if you wish for these programs, and our generosity, to remain sustainable.
The New Colossus
Not like the brazen giant of Greek fame, With conquering limbs astride from land to land; Here at our sea-washed, sunset gates shall stand A mighty woman with a torch, whose flame Is the imprisoned lightning, and her name Mother of Exiles. From her beacon-hand Glows world-wide welcome; her mild eyes command The air-bridged harbor that twin cities frame. "Keep, ancient lands, your storied pomp!" cries she With silent lips. "Give me your tired, your poor, Your huddled masses yearning to breathe free, The wretched refuse of your teeming shore. Send these, the homeless, tempest-tost to me, I lift my lamp beside the golden door!"