Mill's theory of "Individuality" covers several important aspects for the development of liberal democracies in Western nations. "Individuality" and "Liberty" are crucial for progress, whether individual or social. For Mills, individuality is necessary to broaden human happines and at the same time, mantaining broad individual liberty is necessary for the promotion of individuality. On the other hand, individual liberty might be restricted only to avoid people from choosing the wrong way.
In a liberal democracy, there is recognition and protection of individual rights and freedoms (individuality and liberty principles") as well as limitation of the excercise of political power (restriction of individual liberty) thanks to the rule of law.