Christmas 1914 and the Peace that Could Not Be

The question how and why the First World War broke out has filled entire learned libraries, but its no less salient and consequential counterpart—how it got to be so protracted when so many of the illusions that contributed to the outbreak were already shattered by Christmas 1914—has received much less attention, though recent scholarship has begun to close the gap. The aims and anxieties of the respective parties certainly played a prime part on both sides, as did their continued hopes of winning and the complications of coalition warfare. But something more insidious counted for just as much: namely how the horrendous manner in which the war began—grievously disappointing expectations on all sides and producing a staggering five million casualties within only a few months—did not induce, as the standards of textbook rationality might suggest, a readiness to recognise where things were headed and a consequent willingness to change course. Instead of prompting the belligerents to heed the sunk cost principle and cut losses by a timely settlement, the opening months had just the opposite effect, hardening positions that should have been discredited, and leaving the belligerents all the more determined to keep fighting to the bitter end at practically any cost not only to their enemies but also to themselves. How this was possible will be explained, in part, by making connections with prospect and decision theory.