Arnold Kling looks at Libertarianism and Poverty:
What is the fundamental cause of poverty? The Class Oppression view … is that rich people extract and hoard wealth, leaving everyone else poorer. The Pathology view … is that poverty is part of a pathology.
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As a description of reality today, I think that the Class Oppression view has some problems. As a thought experiment, what do you think would happen in America if we were to take the wealthiest 20 percent of our population and exile them — er, us. As part of this exile, we would have to leave all our physical possessions and financial assets behind. Suppose that the 50 million of us are given a country of our own with enough space but no other tangible resources.If you really believe the Class Oppression view, then you would think that without the 50 million hoarder-oppressors, everyone else would be better off, and in their new country the hoarder-oppressors would be in poverty. Instead, my guess is that in twenty years, American poverty would be worse. Meanwhile, in their new country, the hoarder-oppressors would be debating the problem of illegal immigration from other countries, including America.
Something resembling this thought-experiment has been occasionally tried with ethnic Chinese in parts of Asia or Jews in various countries. I believe that the lesson is that expelling wealthy groups tends to leave others worse off, not better off.