wn. They should, therefore, be
small. The nearer they approach the importance of a real attack the less
likely they are to divert a force greater than their own.

It is only their power of diverting or containing a larger force than their
own that justifies the breach of the law of concentration which they
involve.

This power depends mainly on suddenness and mobility, and these qualities
are most highly developed in combined expeditions.

NOTE.--_Diversions_ must be carefully distinguished from _eccentric
attacks_. _Eccentric attacks_ are true offensive movements. They have a
positive object, _i.e._, they aim to acquire something from the enemy;
whereas diversions have a negative object, _i.e._, they aim at
preventing the enemy doing or acquiring something. Being in the
category of the weaker form of war, eccentric attacks are usually made
in greater force than diversions.

EXAMPLES.--_Diversion._--Our raid on Washington in 1815. Landing force,
about 4,000 men. Object, according to official instructions, "a
diversion on the coasts of United States of America in favour of the
army employed in the defence of Canada"; _i.e._, the intention was
negative--preventative--defensive.

2. _Eccentric Attack._--Operations against New Orleans in 1815.
Intended force 15,000 to 20,000 men. Object, "to obtain command of
embouchure of the Mississippi, and, secondly, to occupy some important
and valuable possession, by the restoration of which the conditions of
peace might be improved, &c."; _i.e._, the intention was positive--to
acquire. Compare Rochefort Expedition (diversion) and Belleisle
(eccentric attack) in the Seven Years War.

Note 2.--This distinction gives a threefold classification of combined
expeditions, as used by Elizabethan strategists.

Raids = Diversions.
Incursions = Eccentric attacks.
Invasions = True direct offence.

Compare these with Sir John Ardagh's classification (Report of Royal
Commission on Reserve Forces, 1904):--

"Raids," not exceeding 10,000 men.
"Small expeditions," not exceeding 50,000 men.
"Dangerous invasion," not exceeding 150,000 men.

NATURE OF ULTERIOR OBJECT

From the nature of the ulterior object we get an important classification
of wars, according to whether such object is _limited_ or _unlimited_.

(1) War with _limited object_ ("limi