tion of their fleet wherever that of
the enemy's was, would have seriously shortened the duration
of his command of the Channel, even if it had allowed it to be
won at all. Moreover, attempts to carry out a great operation
of war against time as well as against the efforts of the enemy
to prevent it are in the highest degree perilous.

In war the British Navy has three prominent duties to discharge. It
has to protect our maritime trade, to keep open the communications
between the different parts of the empire, and to prevent invasion.
If we command the sea these duties will be discharged effectually.
As long as we command the sea the career of hostile cruisers
sent to prey on our commerce will be precarious, because command
of the sea carries with it the necessity of possessing an ample
cruiser force. As long as the condition mentioned is satisfied
our ocean communications will be kept open, because an inferior
enemy, who cannot obtain the command required, will be too much
occupied in seeing to his own safety to be able to interfere
seriously with that of any part of our empire. This being so,
it is evident that the greater operation of invasion cannot be
attempted, much less carried to a successful termination, by the
side which cannot make head against the opposing fleet. Command of
the sea is the indispensable preliminary condition of a successful
military expedition sent across the water. It enables the nation
which possesses it to attack its foes where it pleases and where
they seem to be most vulnerable. At the same time it gives to its
possessor security against serious counter-attacks, and affords
to his maritime commerce the most efficient protection that can
be devised. It is, in fact, the main object of naval warfare.

III

WAR AND ITS CHIEF LESSONS[58]

[Footnote 58: Written in 1900. (_Naval_Annual_, 1901.)]

Had the expression 'real war' been introduced into the title of
this chapter, its introduction would have been justifiable. The
sources--if not of our knowledge of combat, at least of the views
which are sure to prevail when we come to actual fighting--are to
be found in two well-defined, dissimilar, and widely separated
areas. Within one are included the records of war; within the
other, remembrance of the exercises and manoeuvres of a time of
peace. The future belligerent will almost of a certainty have taken
a practical part in the latter, whilst it is probable that he will
have had no