American Nations is about the eleven different nations that comprise the United States. The quote referenced is in the Introduction and is part of building the argument that a relatively small group of people can affect the cultural structure of a place long after they’re gone.
This theory was put forth by Wilbur Zelinsky in his book The Cultural Geography of the United States. He called it the Doctrine of First Effective Settlement. He summarizes it:
Thus, in terms of lasting impact, the activities of a few hundred, or even a few score, initial colonizers can mean much more for the cultural geography of a place than the contributions of tens of thousands of new immigrants a few generations later.
I posted this because it reminded me of a study I came across several months ago about how a few early adopters can dramatically affect the trajectory of a young web community. Of course I can’t find it anywhere now, though I printed it out so I have a copy somewhere. When I find it I’ll update this with the title of the report and hopefully a link to wherever it’s hiding online.