Thoughts on Belgium and the defence of the Ardennes

[JBbelgium]

I agree that more time was exactly what the French needed. It would have enabled them to concentrate their troops, including the DCR's, for a better coördinated counterattack. However, at what cost? And who should pay the price, Belgium or France?

[Carl Schwamberger]

The cost would be in proportion to the delay time. As it was the five DLC divisions & several reinforcing groupes or battalions were 'battered' by their two days combat in the Ardennes. Another full day of combat would have seen a noticable portion of their component battalions rendered ineffective, two more days would have seen several of the DLC rendered ineffective, or perhaps destroyed in exchange for actually delaying the German advance. Any Belgian formations that remained to fight with the French, vs withdrawing north west, would have suffered similarly.

To change the subject... Had the German 'sickle cut' manuver somehow failed & been halted east of the Mons/Rheims area I'd supose the Allies in Belgium would have withdrawn lest they still be cut off. In this case would the Belgian army & government have retreated south as well, into France? Or would the government still be inclined to ask for a armistice?

[JBbelgium]

To change the subject... Had the German 'sickle cut' manuver somehow failed & been halted east of the Mons/Rheims area I'd supose the Allies in Belgium would have withdrawn lest they still be cut off. In this case would the Belgian army & government have retreated south as well, into France? Or would the government (IT WAS THE KING NOT THE GOVERNMENT) still be inclined to ask for a armistice?

I think that the Belgian Army would NEVER completely leave Belgium. (just as in 14-18) Also, I don't think that the allies would have broken the connection with Belgian forces. BUT if they did, than the Belgians would probably have pulled back on a small part of the country. They had planned the National Stronghold (Fr réduit national Dutch nationaal bolwerk) along Terneuzen canal, bridgehead Ghent, Scheldt river up to the French border. I suspect they would have taken up a similar position with a southern line perhaps protected by inundations. The North Sea ports would provide a supplyline (as planned).
That raises the question, how long would they have been able to hold on?

[daveh]

On May 10 1940 all men aged 16 to 35 were mobilized leading to c 150,00 men going to recruitment centres (C.R.A.B.) The recruitment centres in Belgium were closed on May 13 1940 and the new recruits were ordered to travel to France, many moving on foot.

The remnants of the 7th Infantry Division were ordered to France after its defeat on the Albert canal.

As Belgian aviation units lost aircraft the surviving ground staff and pilots were ordered to France.

All these movements suggest that the Belgian government intended to continue the fight as long as possible. I agree that the experience of WW1 would have encouraged the Belgians to attempt to hold onto some Belgian territory if at all possible.

As to how long this would have been possible so much depends on the how and why the German advance was halted that I cant provide a reasoned answer.

[A McAuslan]

Hi Daveh,

Just read through this string and cannot agree more strongly with your assessment.
Is there still a presumption out there in some quarters that at April 1940 Belgium, France and UK were cosy allies? In all our speculation we should realise that Belgium viewed its position as having to 'go it' alone and the wholescale abandonment of Belgium to the Germans was never going to be accepted. I believe that many assessments of Belgian forces, and their efforts to defend their nation, are often made without any appreciation of the situation and history of events particularly between September 1939 and May 1940 and are unfair to the Belgians.
As regards JB's question I regret that I believe German tactical doctrine would have sealed off the redoubt and bombarded it with artillery and Luftwaffe till it was reduced. The duration would depend on other operational demands on the heavy artillery and medium bomber force. They would probably have made it a lower priority than Dunkirk - particularly once the evacuation there began.
Cheers,
Sandy McAuslan

[phylo_roadking]

all our speculation we should realise that Belgium viewed its position as having to 'go it' alone

Except it didn't There were the ongoing covert discussions with the Allies - and the Belgian government hoped to raise a HUGE War Loan from the Allies the minute the shooting started and they by default would likely end up on the wrong side of the lines facing the Germans I.E. the same as the Allies! The Belgian government bled money from September on - it called up its reservists and kept them in the field - which meant paying wages (albeit small) and also subsistence payments to soldiers' families to replace thge wage earners that were in uniform. In the meantime - industrial and agricultural production fell...again because of the number of Belgians suddenly in uniform...and as money suddenly vanished out of families' purses - so did government revenue in the form of sales taxes etc.! In the end, the Belgian government gave its soldiers more and more leave per week - another extra day per week was authorised JUST before May 10th IIRC This allowed men to return to work for those couple of days, and keep businesses and trades going...AND put money and food on the table.

Plus - don't forget that when Belgium pulled out of the Locarno pact and declared its neutrality mid-decade....Britain and France had clearly stated THEY would fulfil THEIR Locarno obligations to the defence of Belgium...no matter what Belgium's new status. I don't really see how that declaration....AND the positioning of Allied forces etc. since the war began...AND everything the Allies had said since the start of the war...could have been misunderstood in Berlin OR Brussels!

[A McAuslan]

Hi Phylo,
My point was that in April 1940 that was the Belgian position. I would happily agree that by May 10th there was a de facto alliance and that the French, UK and Belgian forces acted in concert against the German invaders. I may be wrong but I have never found a political declaration of alliance, but one of the causes of the inevitable Belgian defeat was a type of institutional inertia which, with the pace of the German advance, meant that there was never the time to execute any formal document. My assertion that between September 1939 and April 1940 no alliance existed is, I believe, supported by the reaction of the Belgian government to UK overflights. On at least two occasions it was necessary for the UK government to issue apologies for such overflights and, allegedly, on at least one occasion an intercepting Belgian aircraft was brought down in an exchange of fire between UK bombers and Belgian fighters. I do not consider that an intention to try to raise loans in a foreign nation indicates any form of alliance. The UK borrowed huge sums in the USA during both WW1 and WW2 before the USA became a combatant. I also believe that Germany borrowed extensively in at least WW1 in USA. Belgium, so I understand and at least partly, pulled out of the Treaties of Locarno because the French refused to extend the Maginot Line north to the coast. This, from the Belgian viewpoint, acted like a routemap for any invading German army and any mutual defensive arrangements, such as the Treaties of Locarno, would mean to the Belgians that the intention of the French General Staff was to fight the next German Invasion on Belgian territory. Belgium was truly between the rock and a hard place.
They declared 'armed independence', eschewed any form of aggressive equipment, hence no real bombers or tanks(virtually) and their development of a significant number of self propelled anti-tank guns. This was the second of several reasons why the German invasion was destained to be successful. The abandonment of the strategic initiative was, in 1939, a guaranteed route to defeat. What was worse the tactical doctrine of the Belgian Armed forces was also wholly defensive and designed to operate in a 1918 battlefield. Another problem was that trials which were conducted in the Ardennes regarding the effectiveness of armour in that region were carried out. The report on these was wholly dismissive of the effectiveness of armour in that region and the report concluded that armour could not operate effectively in that area. The familiarity of the crews with their vehicles, and the experience and knowledge base of the officer making the determination in the report, are not known to me. This resulted in the virtual abandonment of the Ardennes (I am aware of the sterling efforts of company strength units to hold up the German advance through there but from a 22 Division Army the allocation of stronger units might otherwise have been achieved.) and sealed the fate of Belgium.
As regards the Belgian Status as viewed by Berlin/London-Paris/Brussels at September 1939 it shows how much credence we should place on Government declarations and public announcements. Berlin promised to respect Belgian territorial boundaries!!!!! The London-Paris alliance stationed mobile troops on the Belgian border with orders to advance through Belgium in the event of a German attack. (The act of an ally or friendly nation? - Shades of the dimemberment of Poland by Germany / Russia ) Belgium restated its independence and hoped.
Yes they progressively mobilised their full army. Approximately 14% of the population was in arms. The effect of the Gross National Product was horrific, the exchequer was heamorrhaging money as if a femoral artery had been severed. The economic situation was not sustainable. The effect on individual families was terrible. Yes there were pittances being paid to mobilised troops and their families but they were not sufficient to live on. Troop morale was low and, as well as concessions to leave etc., a scheme to return selected troops to civilian life was agreed. This had a disproportionate effect by releasing many of the officers and so had a greater than anticipated effect on the operational effectiveness of the mobilised reserves.
How about this for an assessment? If one takes the duty of a government's foreign policy as being to protect the interests of the greatest number of its inhabitants as fully as is possible then I would rate the Belgian Government as achieving a 9 out of 10. I do this on the basis that an alliance with the French and UK would have resulted in the advance of French and UK forces to the Belgian/German border. This would undoubtedly have extended the duration of the fighting in Belgium but the Ardennes would still have been virtually undefended. (That was the consequence of a military not a political assessment) The German advance would not have been defeated and much greater damage done to Belgian people and property. The 'armed independence' stance was the best available, in the circumstances - in my opinion.

Cheers, Sandy McAuslan

[JBbelgium]

Greetings McAuslan, interesting thoughts. I would just like to make some remarks.

http://www.ibiblio.org/hyperwar/UN/Belg ... index.html This is a good source for the political situation before 1940.
According to the Locarno agreements of 1925 Belgium had to assist Germany in the event of a French aggression or France in the event of a German aggression. In 1936 (after the reoccupation of the Rhineland) Belgium took up a position of armed independance. They would defend their territory against all agressors and no one would be allowed to cross Belgium to attack a third country. The UK, France AND Germany accepted this new position and guaranteed the Belgian borders. (So any preliminary advance by the allies would be an excuse for the Germans to attack.)

It was pretty obvious that Germany was the main agressor. It was also obvious that Belgium would get caught up in the war against their will due to the Maginot line. So their policy was mainly to try and delay the invasion by staying semi-neutral. Hence the actions against British planes "invading" our airspace. Plus creating a defence in depth so they could hold their part of the line while France and the BEF would deliver the decisive blow.

They declared 'armed independence', eschewed any form of aggressive equipment, hence no real bombers or tanks(virtually) and their development of a significant number of self propelled anti-tank guns. This was the second of several reasons why the German invasion was destained to be successful. The abandonment of the strategic initiative was, in 1939, a guaranteed route to defeat.

I don't think that anyone expected Belgian armoured divisions to march on Berlin. That was the job of France and the UK. Belgium was planning to do their part by holding a part of the line. I agree that more medium + heavy armour and better air cover would have been nice but not crucial. The Cavalry Corps + the Chasseurs Ardennais + the Cycliste frontière + the Light Regiments were all mobile troops with self-propelled guns. That would have been sufficient for local counterattacks.

designed to operate in a 1918 battlefield

Incorrect, see http://www.ibiblio.org/hyperwar/UN/Belg ... um-A1.html
The Belgians were aware of the power of armoured attacks. (But I don't think that they were aware of the impact of close air support.) That is why they based their defences on strong anti-obstacles and in depth. They used the tactic of anti-tank strongpoints. See "la cavalerie motorisée" http://www.mil.be/cav/doc/index.asp?LAN=nl
The same documents reveal that the Belgian High Command was very good at its job. They knew how the actual situation was and they were closer to the front. German breakthroughs were immediatly sealed off and counterattacked. Withdrawals were pretty well organised despite problems of moving ammo dumps etc. (The Belgians did not have ammo dumps in France like the BEF and French had.) Officers and NCO's below regiment level were green, just like the Americans were at Kasserine.

armour could not operate effectively in that area

The conclusion was that armour could not FIGHT effectively in that region. The commander said that he preferred double or triple the amount of T13's over the ACG-1's because they were more manoeuvrable. German panzers did not attack through the Ardennes. The Aufklärungsabteilungen and the Schutzenregimenten did the fighting. The panzers FOLLOWED in their trail.

This resulted in the virtual abandonment of the Ardennes.

Belgium did not abandone the Ardennes. Defending the Ardennes serves only to protect France. Belgium told the French that they wouldn't/couldn't defend them and that the larger French army had to take care of it themselves. Belgium prepared large obstacle zones and would fight delaying actions, that was it. The responsability for the Ardennes lied with the French (and indirectly the British). IMHO this decision was the right one to make. Belgian divisions were already holding two or three times the normal divisional frontline of 6 km. + They needed troops in the back to respond to possible airborne actions (similar to Den Haag/The Hague).

Greetings

[A McAuslan]

Hi JB,
Thanks for a very considered reply. Most of what you say, as well as most of what Phylo wrote, I do not disagree with in any way. I was aware of the import of the 9 Locarno accords but what I was trying to get across, in general, was that, in the impossible situation Belgium found itself in, it did the best job anyone could reasonably have expected.
The only point you make that I genuinely disagree with is the matter of the battlefield in which the Belgian Army was prepared to fight. The concept of anti-tank strongpoints forming a defence was outdated by the German operational doctrines. To be successful it requires an ability, on the part of the defenders, to 'cut off the head' of the attacking forces, envelop them and destroy them. That requires powerful reserve armoured forces and extensive use of minefields and artillery. If Germany had seriously attacked Belgium with her panzers they would not have attacked the anti-tank strongpoints but flowed round them and left them to be reduced by the follow up troops, artillery and the Luftwaffe. Local counter attacks with the types of forces available to Belgian commanders would have been very unlikely to seriously concern the panzertruppen. With green officers at unit level the troops would have struggled.
I do not distinguish between an armoured unit operating in an area and fighting in an area. I make the presumption that armoured operations require that the unit can fight effectively. Again the choice of self propelled anti tank guns, which had an armour thickness that the Panzer 11 could easily penetrate at fighting ranges, is a defensively minded one. The tactical flexibility conferred by a 'proper' tank is surrendered for a defensive aim. The information sharing agreements with Poland would clearly have made the Belgian armed forces aware of the attributes of the Panzers.
However, if I return to my main point, Belgium as a nation had no military solution to its situation. The actions of the French government made Belgium's position worse, not better. In continental terms the UK government was pretty much an irrelevence in the land battle to come. I absolutely agree that Germany was clearly the greatest threat, and that could be seen from the reoccupation of the Rhineland and its remilitarisation.(if such a word exists!)
I hope I have not given you the wrong impression. I have the GREATEST repect for the Belgian armed forces and people both now and for their efforts during WW2. Within the constraints which geography, economics, external world politics and demographics imposed on Belgium the expression 'between a rock and a hard place' does not come close to describing her predicament.
Cheeers,
Sandy McAuslan

[JBbelgium]

I hope I have not given you the wrong impression.

No not at all. I apologise if my reply seemed offensive. I like a good academic discussion and exchange of views.

I should tell you some more about the AT strongpoints (antitankcentrum in Dutch, centre antichar in French). When reading "cavalérie motorisée" I get the impression that the Belgians converted villages into AT centers because they contained crucial crossroads often near bridges across the numerous streams and rivers of Belgium. They used both towed guns and self-propelled guns for this purpose. I imagine it would be a similar concept as the US employed in St-Vith and Bastogne. I think the French used the same tactic later in 1940. It was reasonably succesfull for the French but at that time they had lost their armoured reserve, as you stated.

That requires powerful reserve armoured forces and extensive use of minefields and artillery. If Germany had seriously attacked Belgium with her panzers they would not have attacked the anti-tank strongpoints but flowed round them and left them to be reduced by the follow up troops, artillery and the Luftwaffe.

I agree, thats what Blizkrieg is all about. Striking at the weakest spot. I know that the Belgians used large minefields on some occasions. Defininetly on fixed positions like the KW line both also when retreating west as far as I can remember. Belgium had a decent artillery park and their crews were pretty accurate according to common history. Although the standard divisional 75mm guns are maybe not very effective in indirect fire vs armour.

You might consider the British armoured brigade (the Matilda's) and the French DLM's as the "allied" armoured reserve.
A full frontal attack by the Panzer divisions on the Belgians would, without doubt, have penetrated their lines. But overall would have been better because the Germans would have faced the BEF and the French head on with Belgian pockets of resistance still in their rear (if they could hold out for like 3 days or so).

Overall I agree that a Belgian armoured reserve of their own would have been more efficient than relying solely on allies. Some attempts had been made by the military but were blocked off by politicians. You can read about the ACG-1 story and the Vickers E story in other threads.

Another issue. I have my doubts whether the Belgian industry at the time was able to produce a "real tank". The ACG-1's were produced in France and assembled in Belgium. They definitely produced light armoured vehicles and Cockerill was building a Destroyer Artevelde for the Navy. Does anyone know if armoured plates for tanks differ from armoured plates for ships besides the thickness?

Belgium lacked experience in designing tanks. So they depended on purchasing foreign licenses. But countries usually forbade license production of the more modern tank models. Very few "medium tank models" were actually available for license production as far as I know.

regards

[A McAuslan]

Hi JB,
At no time did I think you were being in any way offensive and I apologise if I gave that impression.
In his lectures on defence against armoured assaults Major-General J F C Fuller specifies - regarding anti-tank zones 'This zone may be as much as 200 miles deep.' (p.135 of Armoured Warfare by JFC Fuller, 1943 Eyre and Spottiswood version). It was no coincidence then that the only nation able to employ this as a realistic defence was Russia. Even today this practical limit to the first stage penetration of a lightning attack persists - Gulf War pause is an example.
The Arras attack was cobbled together by units which had never fought or trained together. The Matildas were 16 Matilda 11 and 56 Matilda 1 and the French forces were 60 Somuas of 3e DLM. The Somua was found to be a much overrated tank - it was thought to be the best all round tank in the world at that time - with the three man crew overworked and armour of 40 mm max down to 20 mm barely adequate. The Matilda 1 shared only its name with the Matilda 11 and was armed only with a machine gun. The Matilda 11 had a 2 pdr turret gun effective at ranges less then 600 metres or more than 1,000 metres (up to about 1,250 metres) against all German tanks of that time. I believe the 'effectiveness' of this attack has also been substantially overrated.
Unfortunately I agree that the Belgian arms industry was probably incapable of constructing a viable medium tank. The only chance it ever had of that died with the SABENA crash which killed Sir John Carden-Loyd.
I would not categorise the Artevelde as a Destroyer and in his book 'Fotoboek Belgische Zeemacht 1946-1996' by Leo van Ginderen/Chris Deldoffe at page 165 it is classified as a 'Fishery Protection Ship'. She was also fitted as a minelayer. With a displacement of only 1,640 tons she would have had no armour plate - no British destroyers had armour plate and I know of no foreign destroyers which could allocate displacement to armour. I do not believe any cross transfer of skills between projects would have been realistic.
To directly answer your question, however, both German tanks and warships used face hardened armour plate. Other nations used different types of armoured plate but it was common for both tanks and warships of a particular nation to employ the same armour plate technology.
The 'beauty' of the lighning attack was that no army in the world understood it as thoroughly as the Germans. No other army was prepared (in its training and tactical doctrines) to seriously contest it - never mind defeat it. In North Africa where the annual Benghazi-Mersa Matrouh handicap was run the essential nature of the warfare was of logistics. Whichever army had the supplies and forces to attack was successful -up to a point where its distances from supply depots became extended and its opponents reduced. The real reason that the El Alamein attack was successful was the Montgomery was able to resist the meddler Churchill's insistance on attacks till he had aggregated sufficient supplies and forces to make the assault work. That was Montgomery's 'genius'.
The geographical constraints on Belgium meant that she was in no position to survive such an attack in 1940. I believe that the most successful early WW2 defence to an armoured attack was by the Finns when they embarassed totally inept Soviet commanders. Here the main stupidity was in allowing the armour to proceed into the enemy positions, in forests, unaccompanied by infantry which the tanks left far behind as they raced forward. Through operations in Poland the panzerwaffe knew the importance of co-operation of infantry and armour in congested areas. The operations in Burma by British Grants and Shermans and Indian infantry brought this co-operation in forest areas to a peak of efficiency against a fanatical defence. Taking this back to the Ardennes the armour would not have been committed till all strongpoints of defence were clearly identified and then an attempt to eliminate them made by Ju 87s bombing on mortar/artillery laid smoke and the lighter tanks would then have been 'shot in' by the PzKpfw 1Vs 75 mm. The series of delays by the Belgian troops were each of relatively modest duration and the 'set piece' assault not required.
The number of foreign licenses and purchases being pursued/considered by the Belgian armed forces was very large and almost certainly beyond the technical capability of Belgium to achieve and I cannot see how there can have been any true co-ordination of these proposals.
I know that several of the modern tanks being brought into service by major nations - French, British etc were not available to foreign governments. Was the AMC 35 not bought because a larger French vehicle was not made available? Probably the only available tank would have been the Polish 14 TP - though a different engine would have been required - it had an armour basis of 50 mm, had 2 machine guns, radio and a main armament of a 37 mm gun (possible uparmed to the Belgian 47 mm?) with a speed of 31 mph and a crew of 4. The main reason I go to Polish equipment is that I know of agreements to exchange information which existed between Belgium and Poland and have assumed a degree of amity between the two nations. (Both hated Germany?) In any scenario, however, the left hook through the Ardennes isolates Belgium from France/UK and the nation suffers even more from the German invaders.
As regards St Vith/Bastogne that defence only worked because the German forces were so short of fuel that their natural attack bound was much reduced and they could not by pass and leave them to be reduced later. The fuel shortage meant that only a proportion of the divisional artillery - about 60% - of the attacking German forces could accompany the assault troops and so the ability to reduce pockets was much reduced. Also the attack was made at a time when the essential air component to an effective lightning attack was not available and the speed of the reaction of the allies by restructuring their forces - it made Montgomery's day when he was given full operational command of American troops north of the bulge - and armoured forces moved south and north to cut the Grmans off from their retreat. The majority of 'destroyed' German AFV's seen in Bulge photos have been shot up as dead targets which were abandoned by their crews - look at the barrel lengths of the guns and the ride height of the suspensions. The suspensions have collapsed because of the heat of fires set by their crews which destroyed the torsion bar suspensions and the barrels are short because the crews drained the fluid from the hydraulic recuperators before firing a last round. Now, fair enough, if I had been in a tank and suddenly saw a King Tiger at a range of a couple of hundred yards I would have shot first and hoped I could escape before it's 88 could bear on me but I know of bazooka trials etc carried out on static examples.
I have enjoyed our discussion.
Regards,
Sandy McAuslan

[JBbelgium]

Major-General J F C Fuller specifies - regarding anti-tank zones 'This zone may be as much as 200 miles deep.

I am confused. Is Fuller saying that 200 miles/321 km is necessary to build a good anti-tank defence or does he mean that such a defence could be up to 200 miles deep?

I don't know that much about ships actually. I'm more of a land forces guy I was just thinking if you can built a warship than you have to be able to build something small like a tank. This source: http://wielingen1991.userboard.net/t1176-artevelde calls it "un vrai contre-torpilleur moderne". In English: a real modern destroyer. But wikipedia (http://en.wikipedia.org/wiki/List_of_World_War_II_ships) calls it a patrol boat. Funny right?

Belgian arms industry was probably incapable of constructing a viable medium tank

I agree.

[phylo_roadking]

I don't know that much about ships actually. I'm more of a land forces guy I was just thinking if you can built a warship than you have to be able to build something small like a tank.

Well - a shipyard could build one...depending how many components or assemblies - engine, gearbox etc. - had to be sourced elsewhere.

But DESIGN one? That's whole different ballgame; a shipyard like Harland&Wolff in Belfast could certainly build them...Cruiser tanks, Matilda IIs, re-turret Lees...but when it came to designing one it made a bit of a mess of the initial A20...

[JBbelgium]

I was actually thinking on a nation base. If a nation can build a warship (engine, armament, electronics...) than a tank should be no problem. I didn't mean the shipyard itself

[A McAuslan]

Hi Folks,
Unfortunately my scanner is hors de combat or I would scan in a few pages of Armoured Warfare. The edition I have was printed in 1943 and contains many additions by Fuller reflecting developments up till then. The whole of section 88 is headed Organizations for Protracted Defence. A few extracts from that section are 'As long as motorized and mechanized armies can maintain their mobility, wars are likely to be short, though possibly not as short as some people think ... ...If I am right in supposing that protracted defensive warfare will mean fighting in the anti-tank zones, then we may be certain that the object of this fighting will be not so much to penetrate the enemy's zone as to keep him fixed in it, so that a secure air base may be established, from which a highly organized air offensive can be launched against the enemy's industrial centres.' He inserts a footnote at this point suggesting that developments both in Russia and UK are showing this to be true. Half a page later 'I will now turn to the anti-tank zones, which I have already discussed in some detail (in summary he is of opinion that the more mobile a defence is the more powerful it is and that the best anti-tank weapon is another tank); nevertheless there are several points which require elaboration. The zone itself will consist of all such territory which if lost will entail surrender. This zone may be as much as 200 miles deep. Obviously, therefore, it is out of the question to cover it with a network of anti-tank defences.' He then goes on to specify that in this area 'all strategic centres will be defended, such as large railway junctions, industrial districts, aerodromes and the capital.' He summarises 'In brief, the protracted defence in mechanized warfare is brought about by entangling the enemy's forces in a tactical net of fine mesh from which, should he break through it, he will find himself caught in a strategic net of wider mesh.'
When Colonel Guderian - as he then was - was submitting his articles on tank warfare to the German military press he was developing Fuller's ideas - and admitted such. Guderian's great advance was to be prepared to ignore the threat to his flanks (this was carried to extreme by Rommel in the French campaign) and to make his advance bound equal to the limit of endurance of his armoured force. He, Guderian, rightly assessed that the panic he could generate in the rear areas, behind Fuller's anti-tank zone, would cause the enemy to collapse as an effective fighting force which he could destroy piecemeal. In the western campaign no effective Fuller anti-tank zone was ever set up and the panzers had their field day with no protracted fighting developing - on the continent.
As regards shipyards making tanks yes, as Phylo says, they often could and did but even if the tank and shipyard were in the same ownership - such as Vickers - the tank design and warship design were totally separate and the design skills were not transferrable.
I regret to have to claim to be a bit of a warship bod. Janes in 1939 listed her under Fishery protection vessels - A new ship to replace the Zinnia was laid down at the Cockerill Yard in Antwerp in 1939. Conway has Artevelde as 'primarily a fishing protection vessel she was to have doubled as a Royal Yacht. She was also well armed and could carry out minelaying and minesweeping duties in the event of war'. Her engines produced 21,700 shp and she was to be capable of 28.5 kts. A 'destroyer' is an abbreviation of the full name of 'Torpedo boat destroyer' and the primary purpose of such a ship was to screen major fleet units from torpedo boat attack. To intercept and sink/drive off enemy torpedo boats before they could launch their torpedoes and threaten the major fleet units. By WW2 they had grown and developed into seagoing attack units which, as well as defending major fleet units could launch torpedoes to attack enemy fleet units. The essential requirements of a destroyer were very high speed - most navies wanted 34-36 knots and found they required 50% more power than Artevelde - all had torpedo-tubes. Although modern ship designations really do require revision a destroyer is still optimised as a protection vessel for major units against surface and air threats while a frigate is protecting against submarine and aerial threats. Possessing no major fleet units there was no requirement in the Belgian navy for a destroyer.
Cheers,
Sandy McAuslan