defence(The act or process of protecting citizens or any geographical area by preparing for or by using military means to resist the attack of an enemy)
differentiation(The development of cells so that they are capable of performing specialized functions in the organs and tissues of the organisms to which they belong)
social differentiation(A concept associated with evolutionary theories of history and with structural functionalism. Societies are seen as moving from the simple to the complex via a process of social change based on structural differentiation)