Slaughter at Chemin Des Dames: Adaptation and Its Limits in 1917


One hundred years ago yesterday (April 16, 1917), the French infantry hurled itself yet again against the German trench system. This offensive (sometimes called the “Nivelle Offensive” for its commander, Gen. Robert Nivelle, the recently installed commander-in-chief of French forces) has been criticized as the classic example of a doomed frontal attack. Not only did it fail, but the experience of yet another defeat shattered the French army and sent it down a path to mutiny.   However, the French tactical and technical innovations employed in the battle have gone underappreciated. That the offensive failed is not evidence of stupidity. Instead, where the French erred was in failing to recognize  failure early and limiting their losses.  The French failure is a cautionary tale for the United States today, given our own optimism about novel concepts and hubris about our prowess (“the finest fighting force the world has ever known”).

The French Adapt: “The Artillery Conquers, The Infantry Occupies”  

By 1917 the war on the Western Front had been grinding on for three years. Repeated allied offensives had produced little movement but high casualties. In 1916, the French had held — but only barely — at Verdun, while the British had mounted a massive, yet unsuccessful, attack, at the Somme.

Two things were clear to French generals as they planned the 1917 offensive: First, they had to take action. German troops occupied a large piece of France and inaction would cede victory to the Germans. Second, a different approach was needed to avoid the failures of the previous offensives. The French decided to employ new operational concepts — the rolling and stationary barrages — and to use leading edge technology — the tank.

Before the war, field artillery in all armies had been light, sparse, and difficult to control when firing beyond line-of-sight. Over the course of the war, the value of artillery soared as technical advances made the guns deadlier, more accurate, and easier to control.  Artillery size increased from the relatively light 75mm howitzer to 100mm, 150mm, and larger. The front became more densely packed with artillery pieces. However, the British Somme offensive had shown that trying to pulverize the enemy front line with intense and prolonged artillery attacks did not guarantee success. The Germans had dug in deep and more than enough of them survived the an intense, multi-day bombardment  to devastate the British troops that followed.

Instead, Nivelle — an artillery officer by training — would use the big guns in a different way.  To retain the element of surprise, he would fire off a short bombardment. Then, as the infantry attack began, the artillery would isolate portions of the battlefield with standing barrages — curtains of artillery fire landing continuously and providing a barrier around any position. The French also refined the rolling barrage. Initially developed by the British, this technique involved the artillery providing a curtain of fire that moved forward slowly with friendly infantry moving in behind it. The barrage would force the enemy to stay under cover until the attacking infantry was on top of them. The combination of stationary and rolling barrages would, in Nivelle’s concept, counteract the two factors that had shut down previous offensives: rapid enemy reinforcement and strong resistance by surviving enemy infantry.

In addition, a group of the newly developed Schneiders would accompany the infantry and take out surviving strong points.  The French (like the British) had spent two years developing an armored vehicle in secret—a classic, potentially war-winning “black” program.  The Germans had nothing comparable.

Nivelle expected a rapid advance and decisive result.  Unfortunately, he said so both often and publically as the battle approached.

The Battle

The attack kicked off on April 16, 1917 and almost immediately bogged down.  The Germans had surmised the location of the offensive beforehand and greatly strengthened their forces as a result.  Operational withdrawals elsewhere had increased German reserves, which were sent to the threatened sector.  To provide resistance in depth, the Germans had built an additional line of trenches out of artillery range.  French tanks proved to be too few, too immobile, and too vulnerable to artillery fire to be decisive (a lesson for those who believe that tanks were the “obvious” answer for breaking through the trenches.)   French failure was evident on the first day when the expected breakthrough to the city of Laon did not materialize.  Nevertheless, the French continued their attacks for three weeks.

On May 5, a French division refused to attack any more.  Four days later, Nivelle suspended the offensive, but it was too late.  More units mutinied and, by the end of the month, 68 divisions were in some form of revolt. On May 15, Nivelle —having staked his reputation on the success of the offensive —  was fired.  His successor, Gen. Henri Petain, barely convinced the dispirited poilus — the French grunts — to stay at the front.   In the end, the line had moved forward four miles at the cost of more than 120,000 casualties.

Insights for the Present

As many articles marking the recent centenaries of the start of World War I and its various battles have reminded us, conventional wisdom still views this conflict as a needless and senseless bloodbath orchestrated by incompetent generals and callous politicians too eager to lead an entire generation into the charnel house.

Although recent scholarship has taken a more nuanced view, the image of incompetence and lack of innovation persists.  This is both unfair in judging French generalship and unhelpful for understanding the dynamics of innovation in wartime.

It is unfair because it judges participants on information that they did not have at the time.  It is easy to look back at events knowing the outcome, to pick the right facts, and to point out what participants should have done. For example, it may seem obvious to us now that primitive tanks would not be decisive or that artillery barrages wouldn’t be able to fully isolate a battlefield. However, judging the events of the past in such a way is to fall victim to what behavioral economists call “the hindsight bias.”

It is unhelpful because it implies that if we were just smarter in the present, we could see clearly enough into the future to avoid stupid mistakes. But that is rarely the case. The data available in the present are wildly contradictory, and many outcomes seem plausible.

For example, someday we will know what happens in Syria. Maybe the self-proclaimed Islamic State will fade away or maybe it will become a global insurgency.  Maybe Assad, weakened by years of war, will collapse. Or perhaps his regime will re-consolidate power.  Maybe a de facto peace will evolve, as exhausted adversaries hunker down in place. Maybe civil war will continue for decades.  One can make a plausible argument for any of these outcomes. Future historians, looking back, will write convincingly about how the outcome was obvious. Today that outcome is far from obvious.

We have similar illusions about generalship: The French generals were stupid, while ours are smart and would never make mistakes like those. Although a comforting thought, it’s delusional.  The French generals were not stupid. They had been trained and hardened by three years of total war. Our generals are no smarter and their record in Iraq and Afghanistan is decidedly mixed. The United States are as susceptible to error as they were, maybe more so since it has not been tested by total war for seven decades.

We can learn two things from the French experience. First, if what you were doing before is not working, do something different. The French made a conscious effort to do this for the Chemin Des Dames offensive.

Second, don’t fall in love with your new concept: If it fails stop.  The French should have terminated the offensive after the first day when it became clear that the expected results were not being achieved.  This is, of course, easier said than done. New ideas gather a lot of advocacy and organizational energy. Think of the momentum that the third offset, Air Sea Battle (now the Joint Concept for Access and Maneuver), distributed naval operations, and shock and awe have generated. If they fail on a future battlefield, it will be a difficult undertaking to discard this deeply ingrained prewar thinking and acknowledge the failure.   But those are the tough judgments that senior leaders are expected to make.  Acknowledging failure of one concept does not require acceptance of strategic failure and defeat. It just means it’s time to try something new.


Mark Cancian (Colonel, U.S. Marine Corps, ret.) is a senior adviser with the CSIS International Security Program. Colonel Cancian spent over three decades in the U.S. Marine Corps, active and reserve, serving as an infantry, artillery, and civil affairs officer and on overseas tours in Vietnam, Desert Storm, and Iraq (twice). He is currently leading a research project on avoiding surprise in a future peer conflict.

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