The quotation from the preamble to the declaration of independence supports the idea that the United States is based on a social contract is this: "Governments are instituted among men, deriving their just powers from the consent of the governed." The aforementioned statements just further proves that there is a contract and understanding between the people and the those in power that their power is simply given by the public.
Mikhail Gorbachev implemented individual freedom policies, he brought about bureaucratic transparency, and to raise psychological activity of economic change. One way he did this was establishing the Sinatra Doctrine.