The naïve view of American frontier expansion generally leaves out most of the details about how the US’s central government—from the early nineteenth century onward—took a very keen interest in how the American frontier was settled, and by whom.
Human Action and Mises' New York University seminar had a huge impact. It's the reason that
Guido Hülsmann on why Human Action embodies the research paradigm of praxeological realism.