Military Lessons of the Spanish War

ALTHOUGH there was an immense development of new weapons and new military methods during the Great War, there has been little opportunity of testing their postwar evolution during the uneasy peace that has followed. Abyssinia taught us something of the value of airplanes, both as a destructive weapon and for the transport of supplies in difficult mountainous country; the tank in that unsuitable terrain was found not to be a success. Mechanical transport and good engineering, on the other hand, won the war for the Italians; without them they could not have reached Addis Ababa before the rains. Deductions from the Ethiopian campaign, however, are apt to be misleading, as the Abyssinians had no air force, no artillery and few modern weapons. Their tactics also seemed peculiarly designed to ensure their early defeat.

It might be expected that the civil war in Spain would have taught some valuable military lessons. Certainly the Powers that sent their material to the support of one side or the other have had an unusual opportunity for a practical test of its efficiency. But accurate information as to the performance of the various weapons is exceedingly hard to obtain; the secrets are jealously guarded. The correspondents with the two forces in the field are not allowed very much freedom of movement and the messages they send are subject to censorship. Even when they are able to write freely, their information is seldom sufficiently exact to allow generalizations on the success of this or that weapon or method of warfare. The peculiar conditions under which civil war is necessarily fought is another reason for avoiding hasty judgments in this case. The failure of tanks in a particular action may have been due to the fact that they were in inexperienced hands rather than to any inherent defect in the weapon itself. On the Government side particularly the militia was hastily recruited from civilian ranks. Few officers possessed of any military knowledge remained loyal and Staff work at the start was conspicuous by its absence. General Franco had the advantage in possessing the majority of the regular officers and a well trained force in the Foreign Legion and his Moors. But until the arrival of the so-called "volunteers" the fighting was conducted on extremely amateurish lines, rather like the early stages of the American Civil War. My attempt, therefore, to extract some military lessons from the campaign must be subject to these limitations.

The first and most unmistakable lesson is the ever increasing power of the defense. The multiplication of machine guns makes a frontal attack nothing but mass murder unless surprise can be achieved. Even the Government's half-trained militia, whose morale at times sank extremely low, was generally able to hold up General Franco's attacks in front of Madrid and inflict heavy losses on his troops. The development of the tank in the Great War restored to the infantry the ability to break through; and it dominated the battlefield until the end of the war. But a new phenomenon has now appeared in the shape of the anti-tank gun. A frontal attack by tanks can now be brought to a standstill, if the anti-tank guns are sufficiently numerous and unless they are blinded by smoke or fog or put out of action by artillery. The battlefields of Spain are the first on which the tank has been confronted by a gun specially devised to deal with it. We thus see the heavy preponderance in favor of the defense, which had been disturbed by the advent of the tank, to some extent restored by the invention of an efficient anti-tank gun.

It is the old story of guns versus armor again. Some new invention gives the one a temporary superiority, which is in a few years nullified by further improvements in the other. So the seesaw continues. A new gas, a new gun, a ray of some extraordinary power or an artificial fog on a large scale may swing the balance once more in favor of the attack. But such an invention is apparently not yet in sight. Meanwhile we may fairly say that the war in Spain has confirmed the view that recent developments in warfare have tended to strengthen the defense.

Another striking feature of the Civil War has been the importance of towns and villages as centers of resistance. No general front has existed; there have been at least four fronts in various parts of Spain, all separate. The Government forces faced westward in Madrid, south at Cordoba and east at Santander. Columns operate in the open country and prolonged struggles take place for the possession of villages. The reason for the prominence of towns and villages as fortresses in the defense is perhaps due to the lack of large masses of heavy artillery on both sides, which in the Great War tended to reduce a village to a mass of dust and rubble in a comparatively short space of time. But the super-heavy artillery was only possible under conditions of siege warfare. It cannot be used to any extent so long as armies manœuvre. Probably European General Staffs will reflect upon this development, concluding that towns and villages can be reconstructed into fortresses, and as a result these will figure largely in schemes of defense like the Maginot line, saving the expenditure of vast sums of money.

Before attempting to draw specific lessons from the employment of tanks in Spain, I should like to make some general observations upon the changes in their use on the battlefield which have resulted from the appearance of the anti-tank gun. In the Great War the tank was the reply to trench warfare, the machine gun, barbed wire and concrete. Even masses of heavy artillery were unable to assure that infantry would get forward without very heavy losses. The tank, particularly when able to effect surprise as at Cambrai and in front of Amiens on August 8, 1918, burst through barbed wire defenses, put the machine guns out of action and enabled the infantry to advance almost unscathed. This tank was a heavy, well-armored and slow-moving vehicle which could be knocked out only by a direct hit from a field gun or heavier piece, and these were not particularly suitable weapons to employ against tanks. The British Army's postwar development of the light tank which has a speed of from 25 to 30 miles an hour completely changed tank tactics. One could then have visions of masses of light and medium tanks moving round the flanks of an opposing army and playing havoc in its rear and with its communications. They were to be employed much as J. E. B. Stuart, the Confederate General, used his cavalry.

The French General Staff were particularly attracted by this idea in case of a war with Germany, and for a time gave up their intention of using tanks only in coöperation with infantry in the attack. Their latest Field Service regulations, however, indicate that they are returning to the earlier view. They believe that the plan of long distance mechanized raids is no longer possible owing to the existence of the anti-tank gun. We must not, however, jump to the conclusion that the day of the tank is over. It will still be an arm of opportunity capable of great things, if its speed enables it to avoid the anti-tank gun or if it can be accompanied into action by a weapon capable of dealing with the latter. There must now be a tank mounting an anti-anti-tank gun, which can accompany the tanks in attack and overwhelm the anti-tank guns with rapid fire. When I attended the German manœuvres last summer I found that they were thinking on these lines; nor has the idea escaped the notice of British tank experts.

In Spain, tanks have hardly proved as successful as was hoped by either combatant. The reasons are various. In the first place they have been in incompetent hands: this was only to be expected. Breakdowns were frequent and maintenance was nonexistent until the trained drivers came from Russia, Italy and Germany. Secondly, the Staff had no idea of tank tactics. They were usually employed in small numbers and without infantry or artillery support. This method of use in the face of a certain number of anti-tank guns as well as other devices ensured the destruction of a large proportion of the tanks engaged. So serious did the resulting discontent become that the tank crews on the Nationalist side were for a time seriously demoralized and wilfully caused mechanical breakdowns. They employed any device rather than face being burnt alive in their tanks, as had been the fate of many of their comrades. Thirdly, although the intervening Powers had obviously sent some of their new material to Spain in order to gain practical experience regarding its efficiency in war, they also dumped upon the two armies a large amount of material of faulty design, things which either had proved defective or had become out of date. This, combined with the rough handling of inexperienced crews, naturally produced further inefficiency.

The number of tanks which each side has acquired up to the time this article is written is very difficult to estimate. Probably the Spanish Government has received about 200 tanks from Russia. The Nationalists have received something like 400 or 500 tanks from Italy and Germany. There is some diversity of opinion amongst observers as to which tanks have proved the best. All are agreed that the 2-ton Italian "Fiat" tank is the least efficient. In many of these the machine guns can only fire straight ahead and the armor is too thin to keep out anything bigger than rifle bullets. This only confirms reports of their failure in Abyssinia. On the whole the Russian light and medium tanks appear to have been superior to the German ones. The German light tank is the same that I saw at their manœuvres last year. It weighs from 4 to 5 tons, is armed with two machine guns, and has a speed of about 30 miles an hour. Its great defect is the thinness of its armor.

The medium-size tanks have rarely been used on either side in Spain except for trench attacks, as it has been thought unwise to commit them without artillery and infantry protection. The Russian one reputedly weighs something like 28 tons and is armed with a quick-firing gun. It is probably heavily armored but little is known of its performance. The general criticism about all the tanks employed is that their armor is too thin and their track-base is too short. Of course there is a close connection between armor and speed. The thicker the armor, the safer the crew; but then speed is necessarily slowed down. Scientists continually experiment to obtain harder steel without an increase of weight, but obviously there are limits to what can be done in this direction. The famous Lord Fisher, former First Sea Lord, said apropos of battle cruisers that "speed is armor." The remark is not entirely true as applied to tanks. The problem is to find the proper compromise between the size and weight of the engine, the thickness of the armor and the fighting power of the vehicle.

Major General J. F. C. Fuller, the great tank expert, wrote an interesting letter in the London Times on April 6 after a visit to the Spanish Front. The following is an extract:

The three types of light tank I have seen, Italian, German and Russian, are mere runabouts, the offspring of cheapness and not of a tactical idea. As regards tank tactics I could discover none. Tanks are used singly or scattered over wide fronts. Up to three weeks ago the largest number used in an attack by either side, I was told, was 15: therefore, there have been no mechanized battles.

So far, from the point of view of mechanization, this war has, I think, proved that the light tank is not really a combat machine at all. It is an indifferent armored scout, but could be made a highly efficient one if its track base were lengthened.

To sum up the experiences of tanks in Spain, it cannot be said that any final tactical lessons have been learnt and we are no nearer a conclusion as to whether a big break through by mechanized forces is possible. But we have gained valuable experience regarding the performance of anti-tank guns and it seems certain that a tank attack will break down against them if they are present in sufficient quantity and if the element of surprise is lacking.

Various means of defense against tanks have been improvised in Spain in addition to anti-tank guns. The Moors and Carlists have been adepts at setting tanks on fire; gasoline is thrown on them, and this is ignited by a hand grenade. The inside of the tank becomes an inferno and the crew has the choice of remaining inside to meet a horrible death or of coming out and being shot down. A similar method is used against the tracks. The synthetic rubber in the track bearings is set alight; this brings the tank to a standstill and it is destroyed by gunfire. Yet another method is to dig a deep wide trench which the tank cannot straddle and from which, once it has entered, it cannot climb out on the farther side. The object of lengthening the track base would be to forestall this method of defense.

I have referred to the anti-tank gun several times. On the Nationalist side the German 22-millimeter gun mounted on a small wheeled vehicle has proved very successful. It is the gun that I saw in use in the German Army. Other German models are also reported to be in Spain, a 37 mm. and a 47 mm. From all the information that can be gathered the German anti-tank gun is a very efficient weapon.

If we study the uses to which aviation has been put in the Spanish civil war we reach conclusions not very different from those reached when we investigate the use of tanks. In the early stages particularly was a similar amateurishness, a similar lack of airplanes (notably on the Government side), and a similar lack of skilled pilots. Later on ample material and well-trained pilots were provided for both sides and air warfare became more intense. But the actual tactical lessons are somewhat obscured by the fact that the anti-aircraft fire was at first negligible and has never been very severe. I think it is true to say that, until Franco's attack upon Bilbao, the moral effect of air bombardment was surprisingly small. Whether it is the fatalistic Spanish temperament or because the bombing was ineffective, the fact remains that the people of Madrid ceased to be perturbed by air bombardment. It must of course be remembered that General Franco did not want to lay the capital in ruins, for he was hoping to enter it at any time. Bombs have usually been directed upon military objectives and upon the western outskirts of Madrid where the Government forces were actually entrenched. Naturally many buildings have suffered and there have been many casualties; but it would be a false deduction from the operations in question to assume that, if ever air bombardment were to take place in a future war in western Europe, it would be of this comparatively mild character. General Franco has certainly never set out to destroy the morale of the people of Madrid by terrorism, as we understand would be the objective of the air force of any Great Power in a European war.

That very capable observer, the correspondent of the Daily Telegraph with the Nationalist Forces, wrote in January 1937:

In an article from Saragossa in the first weeks of the war I expressed the view that the military importance and effect of aviation has been much exaggerated. Subsequent observation during close on six months of war has not changed my view.

Of course it is a terrible experience for civilians to have their homes destroyed by aircraft, but what is the military effect? Again and again planes have attempted to bomb bridges or destroy roads. Invariably they fail.

Not once have I seen an air raid combined with an infantry attack. The planes pass, drop their loads on the enemy's trenches and vanish. An air raid can only last a few minutes, an artillery bombardment can go on for days.

Yet we must remark upon his changed point of view after the bombing of Guernica and the taking of Bilbao. On July 18, the anniversary of the beginning of the Civil War, he wrote:

The chief military lesson of the war has been the terrible moral and material effect on civilians and soldiers of large-scale air bombardments. More and more are aircraft deciding campaigns, but the intense use of aircraft is only quite recent.

In the offensive against Bilbao the Nationalist Commander had made up his mind to use his air force as we expect it to be used in war. With ruthless efficiency his German airmen bombed and machine-gunned the Basques, who were unable to make a reply of any kind whatsoever. They only had one anti-aircraft gun of indifferent quality; and the Valencia Government, for reasons that are difficult to understand, failed to send them a single airplane which could either attack the Italian bombers or retaliate by bombing the Nationalist troops. It was the changed manner in which the Nationalist command used its air force that no doubt caused the Daily Telegraph correspondent to change his views and to realize for the first time what air warfare might really be, particularly in attacks upon great cities. His opinions are confirmed by other observers. The only lesson we can safely draw is this: everything points to the fact that, where air superiority exists, the results will be not less decisive and not less horrible than our imagination has led us to believe. And nothing that happened at Bilbao or Guernica -- bad as it was -- can give any idea of the shambles and destruction that may be produced by large and efficient air forces armed with high explosive, gas and incendiary bombs operating over great cities like London, Paris, Rome or Berlin.

In the early days of the war the Spanish Government employed some commercial machines as makeshifts. The Nationalist equipment was very different. The forced landings of a number of Italian "Savoia" machines on French territory, before the war actually started, made it clear that from the very beginning Franco was being supplied by Italy; and later he was supplied by Germany as well.

The greater part of the airplanes provided for both sides have reached them in spite of the non-intervention agreement and with the connivance of foreign Governments. The arrival of the International Brigade and of Russian airplanes and artillery saved Madrid in the nick of time in November last. The disheartened militia were slowly falling back on the capital without any serious resistance when suddenly they were electrified by the sound of guns giving them support and by seeing fast and well-handled machines for the first time attacking the Nationalist planes in the air. Since then there has been a steady flow of machines to both sides.

The Russians sent both fighters and bomber machines of very high quality to Spain. Their pilots were also extremely good and were on the whole superior to the Germans and Italians on the other side. The "Katiouska" bomber, with a speed of 198 miles per hour, is a particularly good machine. On the Nationalist side there are "Junker 52," "Heinkel," "Savoia," "Caproni" and "Fiat." On the whole the Italian machines are superior to the German ones. On both sides the pilots have been almost entirely foreigners. It is very difficult to ascertain the number of machines now available, but it is probable that Franco has numerical superiority, which is partly counteracted by the efficiency of the Russian pilots and machines. On July 19 it was announced that 170 aircraft were in the air, taking part in the fighting southwest of Madrid.

The comparative failure of the German machines is due to the conditions under which the German air force was created. Prior to Herr Hitler's denunciation of the disarmament clauses of the Treaty of Versailles on March 16, 1935, the German air force was being constructed in great secrecy. No tests of new machines could be made openly and the handicap of producing a ready-made air force in secret, as the German army leaders were determined to do, entailed too much reliance upon theory and was likely to cause serious defects in design. The Germans are excellent engineers and fine and fearless pilots; but no air force in the world could have produced satisfactory machines under such conditions. The war in Spain has been a valuable "trial over the course" for them, and I do not doubt that the defects disclosed are being rapidly put right.

The anti-aircraft weapons supplied and manned by Germans have been very efficient. I saw them in Germany and it is not surprising that their General Staff are obviously very satisfied with them. There is firstly the gun with a calibre of 88 mm., an extreme vertical range of 36,000 feet and a rate of fire of about 15 rounds per minute. Secondly there is the 37 mm. gun which is also used for anti-tank defense. Of all the material that Germany has sent to Spain her anti-aircraft guns have acquitted themselves best. They have been successful against fighter machines below 6,000 feet, less so against bombers that are accustomed to fly at a higher altitude. Their range and height finding instruments must be very efficient and their personnel well trained. On the Government side, air defense has been distinctly inferior both in weapons and in personnel. We are entitled to deduce that the latest patterns of anti-aircraft guns and instruments will act as a real deterrent to air attack and, under favorable conditions, may inflict severe casualties. At the same time it must be remembered that airplanes are getting faster and are able to fly higher. A good deal more experience of the plane-versus-gun problem will be necessary before we can make up our minds that the gun, even in large numbers, can give satisfactorily efficient protection against air raids.

Propaganda is comparatively new as a weapon in warfare but it has been extensively used, chiefly on the Government side. Much of this work has been carried on by Russians, who have long been experts on the subject. The Nationalists, on the other hand, have the priceless advantage of unity of command. General Franco is a leading soldier who won a great name for himself in Morocco. He has a well trained staff of regular officers and there can be no doubt that it has given efficient higher direction. The Government side, on the other hand, has been prey to a long succession of quarrelling, political intrigue and continuous change. No one has known from day to day exactly who was in control. There are also commissars with the military units, who perform political functions and constantly interfere with discipline and with the command of the troops. No commander is safe, and when they get a good soldier like General Kléber, the Commander of the International Brigade, they seem unable to keep him. It is remarkable that the morale of the militia has remained so high in view of the lack of confidence that they must feel about the Higher Command.

The title of this article is "Military Lessons of the Spanish War." I am conscious of the fact that with regard both to weapons and methods I often have had to record that, owing to the conditions under which the campaign is being fought and the difficulty of obtaining technical information, it is premature to form very definite views. Most observers have said that there are no tactical lessons to be learnt. It would be safer, I think, to say that even so there are certain tendencies to be observed. As regards material, it is already clear that the anti-tank gun is destined to cause many changes in the employment of tanks and that the most modern anti-aircraft gun is relatively a greater threat to air power than ground defense has ever been before.