The liberal tradition has its roots in the Enlightenment, that period in the eighteenth-century Europe when intellectuals and political leaders had a powerful sense that reason could be employed to make the world a better place.

States care about relative wealth, because economic might is the foundation of military might.

The German air offensives against British cities in World Wars I and II not only failed to coerce the United Kingdom to surrender, but Germany also lost both wars.

The most dangerous states in the international system are continental powers with large armies.

States have two kinds of power: latent power and military power.

The Soviet Union and its empire disappeared in large part because its smokestack economy could no longer keep up with the technological progress of the world's major economic powers.

A state's potential power is based on the size of its population and the level of its wealth.