Which is more important--security or freedom? why?

It depends on who and where in the world you ask.
Freedom is more important to me. I would not want a system of "security" which "protects" at the expense of my freedom. when the government starts regulating every aspect of your life and especially when the people in power become hunger with it, the government is not regulating the system for the common good and becomes corrupt. Think of every dystopian society... 1984 by George Orwell, Fahrenheit 451, even communism and nazism. The world has experienced "security" through dictatorship and secret police, and banning books, and how to think. John Locke- the great philosopher- believed that men are free and equal and are not guided by green or selfishness, unlike Thomas Hobbes. Locke argues that people had the right to overthrow a government that didn't protect the natural rights to life, liberty and property.