Enclosing the Urban Commons

You don't usually think of cities as being a commons, but here's an interesting perspective that proposes precisely that:

Community development activists, urban planners, and city government officials are increasingly taking note of a disturbing trend: escalating housing costs are forcing lower-income and working- and middle-class residents to leave our nation’s cities. Gentrification and subsequent displacement are rampant. Across the country, millions of us can no longer afford to reside in our major urban areas.

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Or, to put it in the vernacular of the commons, many of our most vibrant urban areas are being “enclosed.” Our cities which once were centers of diversity (ethnically, culturally, and in terms of income levels) are now becoming modern-day analogues to the medieval walled cities of Europe – available to the wealthy elite (and single, young, college-educated professionals with high levels of disposable incomes) while the people who make those cities function (service workers, teachers, police and firemen, city employees) must move to inner and outer-ring suburbs.