The American federal government was for at least a century, and perhaps even longer, primarily involved in defending the new empire and regulating commerce between the republics (or states more generically). By the dawning of the twenty-first century, the U.S. Government had grown both in scope and in the number of employees on its payroll while the governments of the republics had been reduced to functioning as little more than local governments. In other words, Congress had come to act like a state legislature, while the states had accepted their status as mere localities. This fundamental shift with respect to American federalism, as well as the empire-“kingdom”-city arrangement, bears a striking resemblance to the Roman empire. By implication, this similarity might lead us to some conclusions regarding the future the United States within the larger story of the rise and fall of empires.
The complete essay is at Essays on Two Federal Empires.
