The British army was defeated in 1940 for a variety of reasons. Some, such as its paucity of troops, equipment, and air support, and a poor allied plan that thrust the BEF into Belgium and exposed its lines of communication to a devastating German riposte, were beyond its control. But other factors were not. The British were also defeated because they did not foresee how German doctrine and organization would interact with their own on the battlefield. They had failed to take advantage of the lull in operations in the winter of 1939–40 to train for the campaign they actually fought, and their C3I system could not cope with the tempo of operations that the Germans imposed upon it.
By 1939 the British had decided that the way to stop a German armoured attack was not to try to outmanoeuvre the Panzers. Instead, they wanted to create a deep defensive front that would absorb the shock of their attack and prevent them breaking out into open country. The Poles believed that in-depth defences against the Panzers required two lines of defences, the second based on a series of natural obstacles and out of range of German artillery, and that they had to have the support of adequate anti-aircraft artillery, fighter cover, and mobile armoured formations available to counter-attack. However, the BEF lacked the material to produce such a system, although some senior officers deluded themselves into believing that it could cope. In October 1939, Pownall rejoiced that if the BEF advanced to the Escaut it would have no fewer than three anti-tank obstacles upon which it could base its defences and that it possessed a higher proportion of anti-tank guns than either the French or German armies. In fact, 2nd division had only sixty-three anti-tank guns to cover a front of nearly 12,000 yards, giving a ratio of one gun for every 180 yards. German doctrine suggested the proper ratio was one gun for every 34 yards. The divisional commander blithely disregarded such calculations, confident that the Germans were wrong because their doctrine took no account of the plenitude of anti-tank rifles with which his troops were equipped.
Throughout the campaign, the shortage of troops meant that the BEF was compelled to hold far longer stretches of front than was practicable, given its paucity of mobile reserves ready to seal off German penetrations. GHQ hoped that each division would only be required to hold between 5,000 and 6,000 metres of front, and even then conceded that it would only have sufficient reserves for local counter-attacks. On the Dyle, Gort deployed his nine divisions in depth, but the three in the front line were each holding nearly 10,500 yards. On the Escaut, he deployed seven divisions to hold a front of nearly 53,000 yards, or 7,500 yards per division. Each battalion in the forward positions was required to hold about a mile of winding riverbank. On the south-western front, such a density of troops to front was regarded as a luxury. On 18 May, for example, ‘MacForce’, a single infantry brigade supported by two field regiments and a battery of anti-tank guns, was deployed on a front of over 26,000 yards between Raches and St Amand in an effort to deny the Scarpe crossings to the Germans. By the evening of 22 May, Gort had established a thinly held line stretching 45 miles from Gravelines on the coast along a series of canals to St Omer, Béthune, and La Bassée. Just how thinly this was held can be judged when it is noted that the line had no fewer than forty-four crossing-places and each battalion was required to hold an average of over 12,000 yards. The BEF’s greatest extension came on 25 May, when seven divisions, with three in reserve, were trying to hold a front of over 150,000 yards. The fact that the British habitually prepared their positions for all-round defence was of little help. The extended fronts between the localities often made it impossible for them to give each other mutual support.
German tactics were well suited to exploiting these weaknesses. Their operations were characterized by speed and heavy fire-power at the point of maximum effort. As soon as their reconnaissance units had made contact with the BEF’s forward positions, they mounted a series of probing attacks ‘which taps along the front line until a weak spot or gap is found’. Once they found it, they crossed the obstacles covering the British front, established a bridgehead, widened it, and built a bridge so that they could bring tanks and other support troops across. If the reconnaissance unit failed to find a weak spot, their follow-up forces put down a concentration of gun and mortar fire, sometimes assisted by Stukas, and crossed the obstacle behind a curtain of fire. Once they had established a bridgehead, they infiltrated between the British-defended localities, with apparent disregard for their flanks, and pushed mobile troops well forward to further disrupt the defenders by seizing focal points such as towns and road junctions.
The BEF’s attempts to deny roads to the Panzers by holding and fortifying villages was often rendered nugatory by the German practice of employing dive-bombers to drop incendiary bombs on them. The Luftwaffe’s ability to deliver close air support within as little as 45 minutes of the troops requesting it, impressed and demoralized the British. By contrast, inadequate air support handicapped the BEF. The lessons of Spain and Poland had further reinforced the RAF’s dislike of providing aircraft for CAS. The Germans had developed powerful light flak weapons that could exact an excessively heavy toll on aircraft flying such missions. Throughout the winter of 1939–40, GHQ and the War Office fought a largely unsuccessful running battle to persuade the Air Ministry to place more aircraft at Gort’s disposal in case of a German attack. The RAF’s only concession was to accept that in some circumstances the light bombers of the Advanced Air Striking Force in France might be required to act in direct support of the BEF. However, they continued to resist the idea that the whole of Bomber Command should be diverted to attacking German troops if they invaded the Low Countries.
Without adequate fighter support, the light bombers of the AASF and of the BEF’s air component were quickly decimated when they tried to attack German communications centres behind the lines. After the fall of Abbeville, the Air Component was evacuated to England and henceforth the RAF flew missions in support of the BEF from the far side of the Channel. Bereft of adequate communications, this meant that little effective bomber support could be provided for Gort’s troops before they reached Dunkirk and only intermittent fighter cover was supplied as they waited to embark. In contrast, after achieving air superiority, the Luftwaffe played a major role in disrupting the BEF’s C3I system, interdicting its supply lines, and undermining its morale. German air attacks often caused little material damage. The commanding officer of the 1st Tank Brigade at Arras reported that although his formation had been heavily attacked by Stukas, they had knocked out only two tanks. But the psychological impact of even a near miss could be devastating. An infantryman whose battalion was attacked by fifty Stukas in fifteen minutes thought that
An attack by Stukas in these numbers cannot be described, it is entirely beyond the comprehension of anyone who has not experienced it. The noise alone strikes such terror that the body becomes paralysed, the still active mind is convinced that each and every aircraft is coming for you personally, you feel that you have grown so large that they cannot possibly miss.
The RAF did exact a heavy toll of German aircraft in its efforts to protect the allied armies during the evacuation. However, most air battles took place away from Dunkirk and out of sight of the troops on the beaches. Confronted by an enemy against whom they could not retaliate, they arrived in England bitterly angry at the apparent inability of the RAF to protect them.
Shortages of men, material, and air cover only partly explain the BEF’s defeat in 1940. To these must be added another cause, the failure of the army’s C3I system to cope with the high tempo of operations that the Germans forced upon it. The secret of the success of the German blitzkrieg in 1940 was not that it killed large numbers of enemy soldiers but that it destroyed the allied command, control, communications, and intelligence system. What that meant was, according to Brigadier Oliver Leese, who joined GHQ as DCGS on 10 May, that
Decisions had to be made so very quickly and so often could not be confirmed on the basis of the information coming in. Because of these armoured vehicles, the general moves the Germans made were so quick and where you may have a stable situation in the morning, by 7 o’clock or 8 o’clock in the evening, if you did not act and do something, the situation might be irretrievably lost.
He believed ‘we never really got a good working system going in the time with the speed with which the operations went’. This was not just a problem for army headquarters. It affected headquarters at all levels. On 20 May 48th Division’s intelligence summary admitted, for example, that ‘Events have moved so swiftly since the period covered by this report that it is impossible to deduce a course of conduct based purely on the information given’.
The efficient functioning of the British C3I system was impeded by a number of factors. Gort was handicapped by having to act not only as an army commander but also as the C-in-C of all British forces in France. He did not make his own task any easier by the way he organized his staff. Fear of air attack persuaded him to disperse his HQ across fifty square miles around Arras, although its war establishment had been prepared on the assumption that it would be concentrated in a single town. Communications between its various components were already difficult even before active operations began in May 1940. They then became infinitely worse when Gort formed a Command Post forward of GHQ. In particular, the collection and dissemination of intelligence material almost ceased, and the QMG found that he had too few staff officers to perform his duties adequately.
With the exception of I Corps, all the BEF’s higher staffs had to be improvised after the start of the war. Individual staffs took their tone and acquired their efficiency from their commander. Officers who came into contact with them habitually compared the efficiency of Lieutenant-General M. Barker’s I Corps or Major-General H. C. Loyd’s 2nd division unfavourably with that of Brooke’s II Corps or Montgomery’s 3rd division. This was a product of their relative state of training. The BEF’s commanders knew that their troops suffered from a training deficit. In September 1939, for example, the divisions and brigades in II Corps had done no brigade or divisional training. The Territorials who joined the BEF in early 1940 were even worse prepared. It was hardly surprising, therefore, that the CIGS told Gort that ‘he [was] to train his army first when he [got] to France’. But the obstacles in the way of doing so were formidable. They included not only the lack of modern equipment and manoeuvre-grounds, but also the fact that units spent too much time building fortifications along the Franco-Belgian frontier. GHQ was uncertain about the kind of operation for which the troops should train, in November 1939 issuing orders for them to prepare for both a defensive battle against German air, armoured, and mobile formations and for offensive operations against fortified positions. Finally, recognizing the need to train troops in the field was one thing; doing so was another. The pernicious effect of allowing commanders wide latitude to train their own troops was soon visible, for some senior officers failed to translate the realization that their troops needed more training into action. In the winter of 1939–40, whereas 3rd Division (II Corps) held no fewer than four divisional exercises, each of which lasted for several days, 2nd division (I Corps) conducted only two short movement exercises. The upshot was that on the eve of the German onslaught Gort believed that his regular divisions were still not as well trained as their 1914-vintage counterparts and his Territorials were fit only for static operations. Something of the flavour of this failure of imagination was made apparent by the report of two staff officers who visited seven of the divisions that had fought in France.
There was a general complaint that training up to the time of active operations had been lacking in realism and that the written word of reports on German methods was insufficient to prepare troops for actual operations. The continuous appearance of enemy aircraft, the wide frontages of units, resulting in the frequent penetration of enemy troops, and the speed of development of the enemy attack, all surprised our troops and created a tendency to “keep looking over the shoulder to the rear.”
The first symptom of the fact that the BEF could not cope with the pace of operations was the collapse of its communication system. Soon after the start of the German attack, the BEF discovered that its reliance upon cable communications was dangerously misplaced. The British and French believed that telephone communications would be safe because the main French trunk lines were carried by buried cables. However, many of them ran alongside main roads and were quickly cut by German bombing. The telephone system also restricted the movement of GHQ because it could move only to where it could tap into the international telephone system. Even when the cables had not been cut, French telephone operators were not always co-operative, and were liable to break the connection in mid-call or to close down the system entirely when their shift had finished. Attempts to link corps and lower headquarters to the international telephone system failed because the distances involved were too great for the available cable and because lower headquarters moved too frequently. The task of the signal staff was made even more difficult by the propensity of some Operations Staff officers to forget to warn them of impending moves.
The BEF was, therefore, compelled to rely upon radio communications to a much greater extent than it had envisaged before 1939, only to discover that it had too few of the right kind of sets, too few trained operators, and that its security procedures placed an unacceptable delay on the speed of transmissions. After the campaign, the British blamed the French for causing their communications to collapse by insisting the BEF maintain radio silence during the ‘Phoney War’. But that was only one reason why the BEF’s communications failed. By 1944, each infantry division had nearly 1,000 wireless sets. In 1940, they had only 75, and many of those could only transmit Morse, lacked sufficient range, and were too cumbersome for mobile operations. Crucial units within the division, like RE field companies, had no wireless transmitters. Forward of corps headquarters, the transmission of wireless messages in cipher, rather than the employment of simple code words for places, names, and formations, placed an intolerable delay in transmitting information. Wireless, therefore, proved to be no substitute for cable.
Like the rest of GHQ’s staff, Gort’s intelligence organization was improvised at the start of the war. The Germans achieved complete tactical surprise on 10 May and within a few days GHQ’s intelligence staff had virtually ceased to function. The Germans had maintained wireless silence during the ‘Phoney War’ and so the British had no practice at breaking into the German army’s radio traffic. However, they could intercept the many plain text tactical messages that the Germans sent, and, beginning on 22 May, GC &CS began to decipher Luftwaffe Enigma messages. But the real potential of these sources was never utilized. The BEF’s intercept service lacked sufficient linguists who were well versed in German military terms and the dissemination of intelligence between intercept stations, GHQ, and lower headquarters suffered from the same weaknesses as the rest of the BEF’s communications system.
Handicapped by the rapid collapse of their C3I system, senior commanders had to improvise ways of commanding. In the early part of the campaign, GHQ relied upon Number 3 Air Mission, which had been renamed ‘Phantom’ in February 1940, as a general news-gathering service independent of the normal chain of command. As early as 16 May, Corps and Divisional commanders had stopped issuing detailed written orders. Instead they were going forward to subordinate headquarters to hold orders groups, issuing verbal orders, followed, only if time allowed, by brief written confirmation or map tracings showing objectives and boundaries between units. They also employed motor contact officers, who not only delivered orders, but, if they were properly trained, could give their own commander a first-hand account of the position at the front. But there were too few of them, many were not trained, and refugees blocking the roads often delayed their progress.
That the BEF escaped from Dunkirk owed much to the qualities of its commanders. Gort’s ‘mental toughness’ was his greatest contribution to the conduct of operations. Unlike many of his French colleagues, he preserved an equable temperament and inspired confidence in his subordinates. Despite the collapse of his C3I system, he maintained a bleakly realistic understanding of the predicament within which the BEF found itself, and issued the appropriate orders to extricate it from what would otherwise have been a complete débâcle. On 20 May he had the moral courage to oppose pressure from Ironside and the War Cabinet to retreat south-westwards towards Amiens to link with the main French forces. Such an operation would have exposed the whole of his force to a flank attack by the German Panzers. He also acted sufficiently swiftly to improvise scratch formations to protect his rear. On 25 May he had the good sense to withdraw the 5th and 50th divisions from a projected Anglo-French counter-offensive southwards and to use them to plug a dangerous gap between the BEF and the Belgians to the north. In doing so, he forestalled a German attack that would have broken through the BEF’s left flank and surrounded it. Given the odds stacked against him, it was inconceivable that he could have won a great victory. At least he avoided an even greater defeat.
Gort’s divisional and corps commanders were amongst the beneficiaries of Hore-Belisha’s determination to reduce the age of senior officers. Gort’s divisional commanders on 10 May 1940 were on average just over fifty-three years old. After a brief visit to the BEF, Ironside told the War Cabinet on 21 May that ‘On the whole our own High Command were standing up well to the situation, although one or two changes had been made among the corps and divisional commanders’. In reality, what the campaign demonstrated was that Hore-Belisha’s reforms had placed too much emphasis on relative youth as a qualification for high command. In early May, Brooke had decided to replace D. G. Johnson, GOC of 4th division, because he was fifty-six years old. However, active operations began before he could act, Johnson remained, and at the end of the campaign Brooke had no regrets that he had done so. By contrast, as early as 16 May, H. C. Loyd, GOC 2nd division and, at forty-nine, one of the youngest divisional commanders, broke down under the strain. Brooke, who was fifty-seven in 1940, existed on four or five hours sleep each night and still appeared imperturbable despite his own private doubts and fears. By contrast Lieutenant-General Michael Barker, GOC of I Corps, who was a year younger, became ‘very tired and’, in Pownall’s opinion, ‘gave us all a lot of fuss later in the evening about when he could or could not start the retirement . . . He is much too excitable for a Corps Commander’. The breakdowns of Loyd and Barker suggest that the real fault of the pre-war system of selecting senior officers was not that it promoted them when they were too old. Rather, it failed to test their ability to withstand the physical and mental strains of active service and to discard those found wanting.
For all its shortcomings, the BEF’s C3I system operated just well enough to enable its commanders to extricate it from a disastrous situation. The retreat from the Dyle to the French frontier was carried out successfully and under GHQ’s control in a series of bounds from one river line to the next. However, it was fortunate that Von Rundstedt issued his ‘halt’ order on 24 May, for that gave the British vital time to recover some of their balance. The claim later made by Major-General Viscount Bridgeman, who served as GSO1(Staff Duties) at GHQ that Gort ‘never lost control at any stage of the battle’ was an exaggeration. By 26 May, it was common for headquarters to be out of contact with both their superiors and their subordinates. Typical was the experience of Major-General E. A. Osborne, GOC 44th Division. From 26 May until the evacuation, he had no contact with his corps headquarters except for three messages, each of which arrived so late that it was out of date.
The Dunkirk campaign, and the coterminous Norwegian campaign, therefore, revealed a long list of shortcomings in the training, equipment, and doctrine of the British army. On 30 May 1940, in the midst of evacuating his troops from Norway, Sir Claude Auchinleck still found time to write to Sir John Dill, the CIGS, hoping that
I may be able to help you make a new army. It will have [to be] a very different one from our last. War has changed. We are in the same position as were Napoleon’s adversaries when he started in on them with his new organization and tactics. I feel we are much too slow and ponderous in every way.
Auchinleck’s thumbnail analysis of the problem was right. It remained to be seen how effectively the army could find an effective counter to this new Napoleon.