This is a quote from the book "The ​Virtue Of Selfishness" by Ayn Rand
...en private action and governmental action — a difference thoroughly ignored and evaded today — lies in the fact that a government holds a monopoly on the legal use of physical force. It has to hold such a monopoly, since it is the agent of restraining and combating the use of force; and for that very same reason, its actions have to be rigidly defined, delimited and circumscribed; no touch of whim or caprice should be permitted in its performance; it should be an impersonal robot, with the laws as its only motive power. If a society is to be free, its government has to be...
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