It's not just the tyranny of our elected rulers that we have to guard against. We must also guard against the exploitation of minorities by the majority and of the stifling tyranny of political correctness. As John Stuart Mill puts it in the early pages of On Liberty:

Protection…against the tyranny of the magistrate is not enough; there needs protection also against the tyranny of the prevailing opinion and feeling; against the tendency of society to impose…its own ideas and practices as rules of conduct on those who dissent from them…. There is a limit to the legitimate interference of collective opinion with individual independence; and to find that limit, and maintain it against encroachment, is as indispensable to a good condition of human affairs, as protection against political despotism.