UNLIKE THE Schlieffen Plan, Plan 17 contained no stated over-all objective and no explicit schedule of operations. It was not a plan of operations but a plan of deployment with directives for several possible lines of attack for each army, depending on circumstances, but without a given goal... Its intention was inflexible: Attack! Otherwise it arrangements were flexible.

—The Guns of August
© Barbara W. Tuchman 1962
The Macmillan Company, New York
Excerpt from the 11th printing (1972) p. 40-41

Althouth the French did not yet know it, the slaughter at Morhange snuffed out the bright flame of the doctrine of the offensive. It died on a field in Lorraine where at the end of the day nothing was visible but corpses strewn in rows and sprawled in the awkward attitudes of sudden death as if the place had been swept by a malignant hurricane. It was one of those lessons, a survivor realized afterward, "by which God teaches the law to kings." The power of the defense that was to transform the initial war of movement into a four-year war of position and eat up a generation of European lives revealed itself at Morhange. Foch, the spiritual father of Plan 17, the man who taught, "There is only one way of defending ourselves—to attack as soon as we are ready," was to see and experience it. For four years or relentless, merciless, useless killing the belligerents beat their heads against it. In the end, it was Foch who presided over victory. By then the lesson proved wrong for the next war.



—The Guns of August
© Barbara W. Tuchman 1962
The Macmillan Company, New York
Excerpt from the 11th printing (1972) p. 233