It is frequently asserted that after all the main cause of most wars is
rivalry in trade and commercial friction; in short, it is economic. But
it is a curious fact that commerce and industry are the most insistent
on international rules or law to reduce all friction to a minimum, for
peaceful trading is a general benefit to all concerned.
It might be stated in this connection that in historical and political
as well as physical science there is no one cause of anything, but a
chain of causes; for the more we study the world, the closer we find it
related; nothing is nor can be really alone. When we single out a cause
we mean the predominant one, and which is the strongest link in the
chain of causes becomes a matter of opinion, owing to our limited
knowledge of international psychology.
Commercial systems of the world have brought nations closer together,
but political relations have remained much the same; that is, the
advances in diplomacy have been very few in comparison with the growth
of economic relations which makes for peace rather than war.