If there are no human rights a priori of government force, how can tyranny be avoided? In the absence of any deontological justification for normative ethics, there is only virtue ethics.
Liberalism, defined here in the classical sense of the enlightenment values of civil liberty and economic freedom, not a narrow left-leaning ideology, holds individual freedom above all else. In the U.S. both the left and right, except on the extremes of both, fall into the classical liberalism philosophy. Ideas that could be considered pre-cursors to liberalism began developing in the late seventeenth and early eighteenth century. But it was the American Revolution and French Revolution that put liberalism into practice. That means the experiment has been running for a little over two hundred years. Can we draw any conclusions from the results?