fend themselves, need a refuge or point of support near at hand;
which will be found either in certain parts of the sea controlled by
the fighting ships of their country, or in friendly harbors. The
latter give the strongest support, because they are always in the same
place, and the approaches to them are more familiar to the
commerce-destroyer than to his enemy. The nearness of France to
England has thus greatly facilitated her _guerre de course_ directed
against the latter. Having ports on the North Sea, on the Channel, and
on the Atlantic, her cruisers started from points near the focus of
English trade, both coming and going. The distance of these ports from
each other, disadvantageous for regular military combinations, is an
advantage for this irregular secondary operation; for the essence of
the one is concentration of effort, whereas for commerce-destroying
diffusion of effort is the rule. Commerce-destroyers scatter, that
they may see and seize more prey. These truths receive illustration
from the history of the great French privateers, whose bases and
scenes of action were largely on the Channel and North Sea, or else
were found in distant colonial regions, where islands like Guadaloupe
and Martinique afforded similar near refuge. The necessity of renewing
coal makes the cruiser of the present day even more dependent than of
old on his port. Public opinion in the United States has great faith
in war directed against an enemy's commerce; but it must be remembered
that the Republic has no ports very near the great centres of trade
abroad. Her geographical position is therefore singularly
disadvantageous for carrying on successful commerce-destroying, unless
she find bases in the ports of an ally.

If, in addition to facility for offence, Nature has so placed a
country that it has easy access to the high sea itself, while at the
same time it controls one of the great thoroughfares of the world's
traffic, it is evident that the strategic value of its position is
very high. Such again is, and to a greater degree was, the position of
England. The trade of Holland, Sweden, Russia, Denmark, and that which
went up the great rivers to the interior of Germany, had to pass
through the Channel close by her doors; for sailing-ships hugged the
English coast. This northern trade had, moreover, a peculiar bearing
upon sea power; for naval stores, as they are commonly called, were
mainly drawn from the Baltic countries.

But