Romana_ imposed by a
world-wide Empire. That Empire lasted for centuries, and the idea
persisted throughout the middle ages. In modern times Philip II. of
Spain, Louis XIV. of France, Napoleon, and even the Kaiser were
suspected of attempting to revive it; and their efforts provoked the
counter idea, first of a Balance of Power, and then in these latter days
of a Community of Power. The conception of a Monopoly of Power was by
common consent abandoned as impossible and intolerable, after the rise
of nationality, by all except the particular aspirants to the monopoly.
The Balance of Power and the Community of Power--in other words, the
League of Nations--thus became the two rival solutions of the problem of
permanent peace.

THE THEORY OF BALANCE

The discussion of their respective merits naturally led to an inquiry
into what the alternative policies really meant. But inasmuch as the
Foreign Office committee found itself able to agree in recommending some
form of League of Nations, the idea of the Balance of Power was not
subjected to so close a scrutiny or so searching an analysis as would
certainly have been the case had the committee realised the possibility
that reaction against an imperfect League of Nations might bring once
more to the front the idea of the Balance of Power. The fact was,
however, elicited that the Foreign Office conception of the Balance of
Power is a conception erroneously supposed to have been expressed by
Castlereagh at the time of the Congress of Vienna, and adopted as the
leading principle of nineteenth century British foreign policy.

Castlereagh was not, of course, the author of the phrase or of the
policy. The phrase can be found before the end of the seventeenth
century; and in the eighteenth the policy was always pleaded by
potentates and Powers when on the defensive, and ignored by them when in
pursuit of honour or vital interests. But Castlereagh defined it afresh
after the colossal disturbance of the balance which Napoleon effected;
and he explained it as "a just repartition of force amongst the States
of Europe." They were, so to speak, to be rationed by common agreement.
There were to be five or six Great Powers, whose independence was to be
above suspicion and whose strength was to be restrained by the jealous
watchfulness of one another. If any one State, like France under
Napoleon, grew too powerful, all the rest were to combine to restrain
it.

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