The system of communication itself denied any rapidity, let alone instantaneity, of communication when it was most needed, which was in the heat of a… - John Keegan

The effect exerted by paper plans on the unfolding of events must never be exaggerated. Plans do not determine outcomes. The happenings set in motion by a particular scheme of action will rarely be those narrowly intended, are intrinsically unpredictable and will ramify far beyond the anticipation of the instigator. So it was to prove with the Schlieffen plan.

The tragedy of the diplomatic crisis that preceded the outbreak of the fighting in August 1914, which was to swell into the four-year tragedy of the Great War, is that events successively and progressively overwhelmed the capacity of statesmen and diplomats to control and contain them. Honourable and able men though they were, the servants of the chancelleries and foreign officers of the great powers in the July crisis were bound to the wheel of the written note, the encipherment routine, the telegraph schedule. The potentialities of the telephone, which might have cut across the barriers to communication, seem to have eluded their imaginative powers. The potentialities of radio, available but unused, evaded them altogether. In the event, the states of Europe proceeded, as if in a dead march and a dialogue of the deaf, to the destruction of their continent and its civilisation.

Consequences, of course, cannot be foreseen. Experience can, by contrast, all too easily be projected into the future. The experience of the early warriors of 1914–18 – the probability of wounds or death, and circumstances of squalor and misery – swiftly acquired inevitability. There is mystery in that also. How did the anonymous millions, indistinguishably drab, undifferentially deprived of any scrap of the glories that by tradition made the life of the man-at-arms tolerable, find the resolution to sustain the struggle and to believe in its purpose? That they did is one of the undeniabilities of the Great War. Comradeship flourished in the earthwork cities of the Western and Eastern Fronts, bound strangers into the closest brotherhood, elevated loyalties created within the ethos of temporary regimentality to the status of life-and-death blood ties. Man whom the trenches cast into intimacy entered into bonds of mutual dependency and sacrifice of self stronger than any of the friendships made in peace and better times. That is the ultimate mystery of the First World War. If we could understand its loves as well as its hates, we would be nearer understanding the mysteries of human life.