Concepts YOU should know...

Dictators: A ruler or governor whose word is law; an absolute ruler of a state. 
Dictatorship:  The office or dignity of a dictator. || Absolute authority in any sphere.
Communism: A theory that advocates the abolition of private ownership, all property being vested in the community, and the organization of labour for the common benefit of all members; a system of social organization in which this theory is put into practice.
Coup d'état: French phrases frequent in English use.    a. coup d'état (ku deta) [F. état state]: a sudden and decisive stroke of state policy; spec. a sudden and great change in the government carried out violently or illegally by the ruling power
Terrorism: A policy intended to strike with terror those against whom it is adopted; the employment of methods of intimidation; the fact of terrorizing or condition of being terrorized.
Democracy: Government by the people; that form of government in which the sovereign power resides in the people as a whole, and is exercised either directly by them (as in the small republics of antiquity) or by officers elected by them. In mod. use often more vaguely denoting a social state in which all have equal rights, without hereditary or arbitrary differences of rank or privilege.
Welfare State: a country in which the welfare of members of the community is underwritten by means of State-run social services.
Secret Police:  a police organization operating in secret, spec. one owing allegiance to the state or government and used for political purposes.