In the abstract world of American economists, equations run both ways; they believe that by changing the sign of a variable from plus to minus or from minus to plus or the price and quantity of x or y, the direction of historical movement can be reversed.

The historical record suggests that the transition to to a new hegemon has always been attended by what I have elsewhere called hegemonic war.

The opposing tendencies of concentration and spread are of little consequence in the liberal model of political economy.

The dreams of "leaving it up to the market" or of returning to a politically neutral gold standard cannot succeed because the nature of the monetary system has a profound impact on the interests of powerful groups and states. Affected groups and states will always try to intervene in the operation of the system to make it serve their interests.

A prolonged and massive increase in aggregate wealth per capita has taken place over several centuries.

The clustering of technological innovation in time and space helps explain both the uneven growth among nations and the rise and decline of hegemonic powers.

Trade is the oldest and most important economic nexus among nations. Indeed, trade along with war ha been central to the evolution of international relations.