at the time. Instead, the focus lay in creating an army that in terms of both size
and organization was better fitted for European war than the exiguous force
dispatched to France on the outbreak of war. But the emulation of the major
European armies in itself created the need to engage with the operational level of
war. Specifically, it elevated the command level at which the tactics of all arms
were combined to the corps.
TheField Service Regulationshad laid down in 1909 that the basis for the
organization of the field army was the division, ‘a self-contained formation,
comprising all arms and services in due proportion, complete in itself with
every requisite for independent action’. 47 However, European armies regarded
the corps, the next formation up in the hierarchy of army organization, as the
basis of army organization. Britain’s rejection of the Continental model was a
reflection of both the small size of its army and its need to retain an organization
adaptable to small wars as well as big ones. But the British Expeditionary Force
was planned to be six divisions strong, and Haig was of the view that such a span
of command was beyond the powers of one general. 48 TheField Service Regula-
tionstherefore went on to allow for the formation of corps, each composed of two
or more divisions, when several divisions were mobilized. In August 1914, the
British Expeditionary Force was accordingly divided into two corps, and so went
to war with a command structure in which nobody was trained and for which no
staff establishment had been laid down.
At one level, the onset of trench warfare vindicated the British decision to make
the division the key building block of its army. The divisions, whose full wartime
establishment in 1914 was about 18,000 men, achieved steady identities, deter-
mined by the units serving within them, as well as by regional affiliations and
their organizational origins. Moreover, the character of the war pushed the weight
towards the tactical end of the operational spectrum. The coordination of the
three arms—or four with the addition of air power—became the key to opera-
tional success, and this was manifested at the tactical level as armies struggled to
break through. The chances of strategic exploitation of battlefield victory de-
pended on tactical solutions, and the sheer difficulty of its achievement in the
intensely competitive environment of the Western Front meant that strategy as
traditionally defined played second fiddle for much of the war. All the pre-war
doctrinal debates in European armies about envelopments, advance guards, and
lines of operations appeared increasingly recondite and even irrelevant.
Nonetheless, the tactical constraints of trench warfare also elevated the corps
level of command. The key to unlocking trench systems was heavy artillery, a
commodity in very short supply in 1914–16, and even when available in greater
numbers still treated as a corps asset. Nor did divisions have an artillery staff large
enough to produce the sort of sophisticated fire plans necessary by 1916 and after.
The demand was tactical, to generate firepower, but the command level was
operational, and the art was in the coordination of the other arms, particularly
infantry, with what the artillery could do. 49
Trench warfare may, ironically enough, have opened up the operational level
of command in an institutional sense, but it did not seem to do much for
110 The Evolution of Operational Art