The theory is that democratic systems provide a path to peace, and universalizing them would eliminate war and minimize global, political violence - Rudolph Rummel

The citizens of democracies are the least likely to be murdered by their own government; the citizens of totalitarian, especially Marxist systems, the most likely.

We have a solution for war. It is to expand the sphere of liberty.

Known for centuries, a tenet of classical liberalism, the pacific nature of democracy has become largely forgotten or ignored in the last half-century. That democracy is inherently peaceful is now probably believed by no more than a few prominent peace researchers. In part this has been due to the intellectual defection of Western intellectuals from classical liberalism to some variant of socialism, with its emphasis on the competitive violence and bellicosity of capitalist freedoms. Many intellectuals, and in particularly European and Third World peace researchers, have come to believe that socialist equalitarianism is the answer to violence; others, particularly American liberals, believe that if the socialist are wrong, then at least democracies are no better than other political systems in promoting peace.