A What If Case Study – Dunkirk 1940

Longtime readers of the blog may remember that I have often used the Dunkirk Campaign of 1940 to provide context and perspectives on events in the Civil War. I’ve blogged about Lord Gort, the British Expeditionary Force (BEF) commander, in terms of leader decisions and the pressure of command. An example of a British doctor left behind with wounded helps relate to Savage Station in 1862. I’ve also used Dunkirk as an example of battlefield fortitude and noted it as part of the Zouave battle record.

Dunkirk also contains one of the more interesting “what if?” scenarios of the early part of World War II – specifically, the German panzer divisions halting for 72 hours beginning on May 24, 1940. Examining this situation illuminates the complex decisions facing both Gort and the Germans, and provides a framework for considering other “what if?” scenarios.

First, let’s lay out the situation. On May 10, 1940, German troops attacked Allied forces in France, Belgium, Luxembourg, and the Netherlands. Ten days later an armored thrust reached the channel and cut off the BEF, First French Army, the Belgian Army, and assorted other units (totaling approximately half a million men) from the rest of French forces in France. (See map.) The German forces put guard forces on the southern front, while several panzer (tank) divisions slashed northward in an effort to cut off the Allies from the Channel coast. Simultaneously, German infantry divisions attacked the Allies from the east.

Now, let’s look at the key moment, or turning point, that produces the “what if?” scenario. In three days, the German troops made great progress. British garrisons were bottled up in Calais and Boulogne by 1st and 2d Panzer Divisions, and elements of the 1st penetrated to within 10 miles of Dunkirk. However, they were largely out front of the rest of German forces. On May 24, Adolf Hitler personally ordered his panzers to halt their advance, a stoppage that lasted 72 critical hours. He felt the estimated 100,000 Allied troops in the pocket could be handled by German air units. During that time Gort solidified a defense and set the BEF in motion toward Dunkirk and evacuation. Boulogne’s garrison was evacuated, while Calais held out until May 27. From May 26 to June 4, 338,226 British and French troops escaped to England, despite German ground and air efforts to stop them. Ever since, Hitler’s “Stop Order” has been one of the great “what ifs?” of the first 12 months of World War II.

Given the above, the great question is: why did the Germans forsake an attack? What is likely to have happened had they attacked? Answering the latter question helps illuminate the answer to the former.

Alternate scenarios have 1st Panzer Division striking for Dunkirk and capturing the port quickly, but little beyond. Assuming that happened, and supporting attacks happened along the line further east, it is likely that within a day or two after May 24 the Germans would have made important gains. However, if the Germans wanted to cut off the BEF and its allies from the coast, they needed to secure a strip of land along the Channel connecting the panzers with the infantry of Army Group B coming from the east. As Army Group B was making slow progress, such a move would have needed most of the available panzer divisions to execute.

Assuming such a cordon was made, Gort would have attacked with everything he had to get through. On May 25 he decided to “operate toward the coast,” and for several days before had tried to break out southward to the French. He was a determined man, a Victoria Cross recipient for leadership in World War I, and in the historical operation demonstrated powers of leadership and decision that saved the BEF. He would have succeeded or literally died trying. Also, any attack toward the coast through a German corridor would have had the support of the Royal Navy from the Channel and the Royal Air Force from England – both factors that helped the historical evacuation.

If the Germans had captured Dunkirk and stopped, there were still miles of beaches around La Panne and Nieuport available to Gort and the BEF; historically, a significant percentage of the Dunkirk evacuees left via the La Panne beaches. The port of Ostend was still in Allied hands at that time, and could have been used as a base or evacuation point. Exercising either or both options would have saved much, possibly matching the historic result.

Of relevance are German experiences in Poland in 1939 and elsewhere during the 1940 campaign. Air power had a demoralizing effort on many Allied troops, weakening their desire to resist and in some cases speeding surrender. However, many pocketed Polish units fought with resolve until overwhelmed, even launching counterattacks and breakout attempts up to the end.

It is well documented that many senior German generals were worried about French troops to the south, the strength of which they overestimated. British attacks at Arras on May 21 had given two good German units anxious moments, and there is evidence it made senior leaders nervous. On top of all that, infantry support for the panzers was lacking and many tank crews and equipment needed some rest and refitting. Germany also had only 10 panzer divisions in its army, and 9 stood committed in the Dunkirk area.

Given the above considerations, the Stop Order becomes more understandable. Germany would have staked the armored core of its army in a battle along a narrow stretch of coast, without support if something went wrong, facing several hundred thousand desperate Allied troops under leadership determined to get out.

This framework is applied to a case from 1940, which coincidentally occurred during the 75th anniversaries of the Grand Review in Washington and E. Kirby Smith’s surrender in Texas. But applying these kinds of questions and considerations is useful in other eras, including the Civil War. In all cases, it helps understanding of the people and events of the past, and how things happened as they did. This is the value of considering “what if?”

12 Responses to A What If Case Study – Dunkirk 1940

  1. Thanks for the perspective, although I was under the impression that the Reichsmarschall Göring convinced Hitler that his Luftwaffe would deliver the Schwerpunkt to the BEF, which was the first of many bad calls, e.g., Operation Adlertag should destroy the RAF and result in British capitualtion, the surrounded Sixth Army at Stalingrad could be adequately supplied by air, und so weiter. Hitler was still suspicious of the loyalty of his Whermacht generals, and allowing them the laurels of destroying the British army could counterbalance his absolute power. After all, Generaloberst Ludwig Beck, the Chief of the General Staff of the German High Command confronted Hitler and resigned in 1938 (later killed for his part in the July 20th plot against Hitler). Hitler’s mismanagement of his military forces gave birth to the rumor that Ike’s staff considered Hitler the best general the Allies had (a comparison to Bragg?). So, the thoughtfulness of Hitler’s Stop Order may be somewhat over exaggerated.

    1. You’re right about Goering, and I allude to his overconfidence in the Luftwaffe in my “air power” comment. Less well-known is the German Army’s nervousness about just how far out in front the panzers were, which is covered well in Alistair Horne’s TO LOSE A BATTLE.

  2. Here is the main question as I see it: does the “What if” involving the stoppage of the Panzers represent a viable chance for the Nazis to win the war? Or to at least contribute to them knocking Great Britain out of it? While we can’t ever know what would have happened had something else took place other than what we know did, in this case, Great Britain is not taken out of the war, while the prisoners the Germans take and the other casualties they inflict increases significantly. The reason is fairly simple. The key to defeating GB laid in defeating their Navy and air forces. Germany had no way of bringing their vaunted Panzers to bear against GB itself simply because they had no way to transport them there, i.e., they had no way to invade so long as GB’s navy was intact, and that applied to its air power too. So the Dunkirk “what if” based on the Panzers not stopping is probably relatively easy to dispose of.

    I will add this though. The Dunkirk “what if” scenario of the Panzers continuing to assault is a viable question in itself. I’m of the belief that many if not most of the others that get brought up on venues like this do not accomplish that. But given the German success at that point in WW2, and the peril that GB faced, asking “what if” Germany kept attacking is not only fair, but it is necessary. And that is a significant difference.

  3. Tanks cannot advance without adequate Infantry support. You can look to the first two months of the Ukraine war to see what happens when tanks advance without Infantry in support. It is a fundamental precept which the Russians largely disregarded.

  4. Well analyzed. Too often in the past we gave a pass to the higher command of the Wehrmacht because of of our postwar need for a strong Germany to counterbalance the Soviets. So the canon of the Honorable German Army against the incompetent (fortunately dead) Hitler and Goering was swallowed for decades

  5. OK, i’ll take a crack at this “what if” … in the interest of full disclosure, however, I was in my younger days an adherent to the “legend” that German halt order was a big-time tactical faux pas … and the British only got away at Dunkirk because of it … I have since changed my tune.

    Here goes: Other than giving the British and French defenders some breathing room, the 24 May halt order to Army Group A was not a decisive factor in the “miracle” at Dunkirk … in other words – order or no order, the outcome would have been the same. Here’s why:

    Bad Tank Country — The terrain around Dunkirk was low lying, soggy and networked with ditches – ground suited to defenders … so what worked in Army Group A’s dash across France to the channel wouldn’t work at Dunkirk … for example, a French infantry regiment with supporting arty and anti-tank guns turned back the 9th Panzer Division on May 30th twice.

    Allied Pluck – Crediting the halt order as a critical factor assumes little to no allied agency – not a good assumption … the British, the French and Gort, in particular, were responsive, flexible and innovative … i.e., Gort moving the British 5th and 50th divisions to stop a break-through in the Belgian sector on the 26th , the 2nd Division holding off four German divisions, three of them armored, on the 30th , and the French in Lillie tied down seven German divisions until June 1st , even after the pocket closed behind them and they were surrounded. … therefore, it’s reasonable to assume similar Allied resolve had Army Group A attacked on the 25th

    German Problems:

    Maneuver or Attrition Warfare? — The German plan was based on speed, surprise, avoiding allied strengths and exploiting their weaknesses … this worked superbly throughout the 6-week campaign, but not at Dunkirk … the allies were not surprised, speed was not an issue, the allies had interior LOCs and the Germans were confronted with strong positions in their front — not conducive to their preferred doctrine of maneuver warfare.

    Who’s in Charge? — With Army Groups A and B in proximity, there was no coordinated plan to reduce the Dunkirk pocket and no single commander to oversee and coordinate such a plan … the Germans did appoint a commander until the 28th – too late … by then the allies had evac’d 200K soldiers … so with no joint plan, it’s likely the allies could have held against piecemeal German attacks.

    Consider the Big Picture — Third, it’s easy to forget that Dunkirk took place in the context of the campaign to conquer France and the Low Countries which take another two weeks … the Germans could not further attrite vanguard formations at Dunkirk … so, by the 28th , Guderian was already pulling armor in anticipation of Plan Red.

    Tired Soldiers, Broken Tracks – Army Group A had been in the fight for almost two weeks … their soldiers were exhausted and about half of his tanks were down … fresh infantry and maintenance personnel – most of which were not mechanized – were many miles behind … not the formula for success against a dangerous opponent in prepared positions with lots of artillery.

    That’s my “what if” story … the Allies controlled their own destiny at Dunkirk through leadership, resilience, innovation and adaptability, ashore and at sea … sure, the 24 May halt give them a bit of a breather – who doesn’t need a breather … but it was British, not the Germans, who created the miracle at Dunkirk.

  6. Very good points but I’ve never assumed that this order was based strictly on a military assessment. It came from somebody whose military “training” and experience were as a low-level non-com on the Western Front. As we know, he also had a bizarre notion that Germany and Britain were somehow destined to be “allies” of a sort and stayed his hand later that year in launching Operation Seelowe. (Then there’s the decision regarding the Sixth Army and Stalingrad). It’s hard for me to look at these solely by examining the military rationales. In other words, the May 24 order may well have made sense from a military perspective but to some extent that may have been fortuitous.

  7. thanks for your comments John … years ago i read the same interpretation about the 24 May halt — i.e., Hitler wanted to allow the Brits to save face and thereby “allowed” their evacuation by halting the panzers … there are a few issues with that notion … first, the halt only affected Army Group A in the west … Army Group B continued their attack on the eastern side of the pocket … second, there were two other halts — at Montcornet on the 17th and Arras on the 21st — both after French and British counterattacks on Army Group A … while both failed they reinforced German discomfort about the security of their southern flanks … at one point Rommel’s advance was 75 miles long and only one mile wide — that’s pretty skinny … so, higher army HQ military concerns about allowing their infantry to catch-up are understandable … it also puts the third halt on the 24th in context … finally, i don’t think the Germans believed the British could pull off an evacuation of that many soldiers across the beach — 338K guys in a little more than a week.

    1. Mark: You make good points. To be clear, I’m not completely buying into the non-military rationale and I’ve never bought into the “saving face” theory. But I think it’s more complicated than that and it’s impossible to completely exclude Hitler’s occasional waffling about Britain when we know who was ultimately pulling the switches. There were several times during the war when decisions were made that didn’t fully comply with the Wehrmacht textbook.

      1. i agree … race and the idea of Volksgemeinschaft (ethnic brotherhood) were never far from Hitler’s mind … and he clearly regarded Britain as part of that brotherhood … so, it’s possible that motivated much of his thinking and decision making.

  8. I have to agree with Mark that the British created the miracle act Dunkirque.

    The fact is that tank warfare is accompanied by infantry to combat any anti-tank units the enemy may have. Combined combat doctrine was part of the German Blitzkrieg Offensive. The panzers had gotten ahead of their infantry.

    An analogy from the field of logistics is, you don’t out-run your supply line.

    What this evacuation did was give a tremendous boost to British morale, in the face of the surrender of Great Britain’s continental Allies, the Poles who were invaded by both Nazi Germany and Soviet Russia, and France which again had suffered battle field casualties.

    Churchill admitted that wars are not won by evacuations, but in the same speech declared “[We] shall not flag or fail. We shall go on to the end, we shall fight in France, we shall fight on the seas and oceans, we shall fight with growing confidence and growing strength in the air, we shall defend our Island, whatever the cost may be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender.”

    What is forgotten in this evacuation is the massacre of members of the Royal Norfolk Regiment who surrendered to the advancing Germans and then were machine-gunned to death, the survivors being bayoneted or shot by pistol. Only 2 men out of 99 survived to tell the story. The German who gave the order for this massacre was hanged after the war. And rightfully so.

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