Why is the United States called a land of settlers?

There have been many immigrants in the United States at all times. It is difficult to understand the immigration figures for a century and a half. The increase in the number of immigrants appears to be significant, from 2.2 million in 1850 to nearly 43 million in 2016. But it’s worth remembering that in the mid-19th century, the United States had only 23 million inhabitants, up from nearly 326 today. At the end of the 19th century, powerful nativist movements emerged that fought against immigration, but their efforts were unsuccessful, so today the United States is considered a country of settlers.