In the late 19th and early 20th century immigration waves, there were many skilled artisans and craftsmen flocking to our shores who brought with them the ability to make such things. In the age of heavy industrialization and mechanization, there was still value in handcrafted unique labors and found a market for such.
Today's immigrants are skilled in assassination, kidnapping, drug running and human trafficking.
When I worked at IBM Research in NY, our lab was designed by Eero Saarinen. It was an arc of stone quarried from the 200 acres with a curve of glass in front of the stone. They used Italian-trained stone cutters in the construction.
IBM T.J. Watson Research Center NY Music Video - 1987 - Nightnoise
https://youtu.be/wjugl_6PngM