altering political questions, let the reader take his atlas and consider
the case of that impregnable fastness, that great naval station, that
Key to the Mediterranean, Gibraltar. British boys are brought up on
Gibraltar and the Gibraltar idea. To the British imagination Gibraltar
is almost as sacred a national symbol as the lions in Trafalgar Square.
Now, in his atlas the reader will almost certainly find an inset map of
this valuable possession, coloured bright red. The inset map will have
attached to it a small scale of miles. From that he will be able to
satisfy himself that there is not an inch of the rock anywhere that is
not within five miles or less of Spanish land, and that there is rather
more than a semicircle of hills round the rock within a range of seven
or eight miles. That is much less than the range of a sixteen-inch gun.
In other words, the Spaniards are in a position to knock Gibraltar to
bits whenever they want to do so, or to smash and sink any ships in its
harbour. They can hit it on every side. Consider, moreover, that there
are long sweeps of coast north, south, and west of the Rock, from which
torpedoes could be discharged at any ship that approached. Inquire
further where on the Rock an aeroplane can land. And having ascertained
these things, ask yourself what is the present value of Gibraltar?

I will not multiply disagreeable instances of this sort, though it would
be easy enough to do so in the case both of France and Italy as well as
of Great Britain. I give them as illustrations of the way in which
everywhere old securities and old arrangements must be upset by the
greater range of modern things. Let us get on to more general
conditions. There is not a capital city in Europe that twenty years from
now will not be liable to a bombing raid done by hundreds or even
thousands of big aeroplanes, upon or even before a declaration of war,
and there is not a line of sea communication that will not be as
promptly interrupted by the hostile submarine. I point these things out