the French army. A decisive victory would put pay to French military power. Of
no less significance, it would convince other powers, Austria in particular, to let
half-drawn swords return to their scabbards.
Moltke expected to have about 360,000 men for his offensive; superior num-
bers, but not exactly overwhelming, especially for an attacker. His corresponding
decision was to concentrate two armies—in the event a single, oversized 2nd
Army—that would advance in two echelons, ready to attack to its front or swing
to either flank. On the right, a 1st Army of two corps would cover the 2nd’s
advance and be ready to strike against the French left flank should an opportunity
arise. The 3rd Army, with a final strength of three Prussian and two-and-a-half
South German corps, was to serve as a left-flank guard and itself engage a French
flank should opportunity offer.
In specific terms, Moltke planned to swing south of the French fortress of Metz,
then advance on the Moselle. A major battle should take place before reaching the
river, and ‘thereafter nothing can be predicted in detail’. This approach is often
cited in general works as illustrating Moltke’s aphorism that no plan survives
contact with the enemy. It also illustrates the chief of staff’s contention that,
therefore, the initial plan must be a good one! He provided regularly updated
timetables for the advance of each corps—detailed to a point of specifying what
locations each formation would reach on a particular day. He insisted as well that
the corps’ marches on entering the theatre of operations be specifically regulated
from above: strict control of the campaign’s initial stages. Control was the best
available measure against the development of something like a continuous front;
with Prussia’s three armies pushing the French back steadily—but too slowly to
fulfil the war’s policy objectives. 29
Once the campaign began, its circumstances changed as the opposing armies
manoeuvred, engaged, and reacted. Calling this the collapse of Moltke’s war plan
may be a bit strong. 30 But certainly the chief of staff repeatedly confronted the
unexpected. Like the fine whist player he was, Moltke kept his head and read his
cards even when Prussia’s government, in the persons of its king and its Chancel-
lor, Otto von Bismarck, was looking over his shoulder. If his game plan varied
from hand to hand, the changes were in a consistent context: maintaining the
goal of destroying the French army.
After the initial battles on the frontier at Spicheren, Wissembourg, and Wo ̈rth,
the French retreated in two directions. 31 Five corps fell back towards the fortress
of Metz. Three others withdrew in the direction of the fortified camp of Chalons.
Moltke concentrated on the larger force. The 1st Army and part of the 2nd would
push the French directly. The 3rd Army reinforced by two of the 2nd’s corps
would swing up from the left into their flank and rear. When the French slowed to
engage in a half-hearted rearguard fight at Borny on 14 August, Moltke reacted by
designating the 2nd Army as the pivot of a flank movement around the fortress
of Metz and against the main French line of retreat towards Verdun. The chief
of staff’s concept remained operational. He had no plans for a major battle on
16 August. Vionville–Mars-la-Tour was the consequence of an aggressive corps
commander implementing his notion of initiative and mission tactics by
42 The Evolution of Operational Art