fourteenth-century revolts of French and English peasants, are not
events which come suddenly and unexpectedly; each such outbreak is like
the eruption of a volcano, a symptom of subterranean forces continually
in conflict. The state of peace in medieval society was a state of
tension; equilibrium meant the unstable balance of centralising and
centrifugal forces. And this was one reason why wars, condemned in the
abstract by the Church, were frequently regarded with favour by sober
statesmen and by idealists. In more ways than one a successful war might
serve to heal or salve the feuds of rival classes. It offered an outlet
for the restless and anarchic energies of feudalism; sometimes it ended
in conquests with which the landless could be permanently endowed. It
might offer new markets to the merchant, a field of emigration to the
peasant, a new sphere of influence to the national clergy. Better still,
it might evoke common sentiments of patriotism or religion, and create
in all classes the consciousness of obligations superior to merely
selfish interests.

Such statecraft may perhaps seem rude and barbarous to us. The idea of a
nation as a system of classes, and of national unity as a condition only
to be realised when all classes combine for some purpose extraneous to
the everyday life of the nation, is foreign to our thought. We believe
that by making war upon class privileges we have given to the State a
less divided and more organic character. We maintain that the State
exists to realise an immanent ideal, which we express by some such
formula as "the greatest good of the greatest number." But we are still
so far from a reconciliation of facts with theories that we must
hesitate before utterly condemning the medieval attitude towards war. In
place of classes we have interests, which are hard to unite and often at
open variance. Our statesmen balance one interest against another, and
consider war legitimate when it offers great advantages to the interests