Captain Basil Liddell Hart, better known as the ‘alchemist of war’, was a hugely influential British military thinker in a career that spanned the 1920s to the 1950s, a remarkable epoch in global history. Educated at Cambridge, Captain Liddell Hart had joined the King’s Own Yorkshire Light Infantry in 1914 and was invalided by concussion injuries caused by shelling in 1915. He returned to serve in the Battle of the Somme, where he was wounded and gassed, before being posted to write training manuals under General Sir Ivor Maxse. He was eventually invalided out of the British Army in 1924, becoming a journalist for The Daily Telegraph, and then took up writing on military history with enthusiasm.

His advocacy in his scholarly work of an ‘indirect strategy’ over direct, frontal operations, was a reaction to the high casualties of the Western Front in the First World War. But his ideas were not simply about physically outmanoeuvring an opponent. Instead he pushed for a psychological scheme: to strike from unexpected directions, to generate strategic dissonance, and to induce paralysis. In this sense, Liddell Hart retains much of interest to us in our information age. His work reminds us that conflict and confrontation have not been limited to physical threats and manoeuvres, but to strategic pressures across a variety of domains.

Liddell Hart believed that distilling historical insights of strategy and operations would offer the chance to avoid the costly disasters of modern war and ensure a more cost-effective route to success. He imagined technological solutions in the form of air power and mechanised land forces outflanking and shocking an enemy at the tactical level. This would be complemented by taking indirect strategic ‘ways’. Like his contemporary J.F.C. Fuller, Liddell Hart considered concentrations of air and armoured forces driving deep into enemy territory to destroy their ‘nervous system’. The psychological aspects of this were central, since acquiring an advantage demanded moves that were unexpected, with precise attacks at the most vulnerable points.

In the opening of his popular work Decisive Wars of History, originally published in 1929, Liddell Hart asserted: ‘throughout the ages, effective results in war have rarely been attained unless the approach has had such indirectness as to ensure the opponent’s unreadiness to meet it. The indirectness has usually been physical, and always psychological.’ He concluded, famously: ‘In strategy, the longest way round is often the shortest way home.’

Liddell Hart’s career in military thought evolved to reflect changes in the character of war, from the horse drawn 1910s, through the mechanised 1930s and jet-propelled 1940s, to the nuclear age. He possessed a considerable range in his grasp of military history. His success was in his ability to see such significant changes through a clear and consistent framework, and, crucially, to be able to apply that history to the present.

He set out to become a renowned specialist in military affairs, which his critics have been quick to ridicule. Yet it is worth noting that Liddell Hart was not driven solely by ambition. As a witness to the heavy losses of the First World War, he was determined to find methods of conducting warfare at a lower cost. The objective was always, he stated, ‘to produce the enemy’s increasing overstretch, physical and moral.’ Famously, he wrote: ‘Nations do not wage war for war’s sake, but in pursuance of policy. The military objective is only the means to a political end. Hence the military objective should be governed by the political objective … The objective in war is a better state of peace – even if only from your own point of view. Hence it is essential to conduct war with constant regard to the peace you desire.’ Liddell Hart believed, like many of his generation including JFC Fuller, that waging a war that left the country in a worse state was evidence of a strategic failure, since strategy was ‘the art of distributing and applying military means to fulfill the ends of policy.’ The art of strategy is still concerned with achieving significant political advantages without recourse to war or, at least, at minimum cost. The current East-West confrontation through ‘sub-threshold’ activities, sometimes known as grey zone or hybrid warfare, fits precisely within Liddell Hart’s conception.

Liddell Hart felt that an economical approach should be reflected in the conduct of operations. Democratic nations must wage war in a more flexible way than authoritarian states, he reasoned, making every effort to avoid unnecessary losses. His criticism of the mechanistic approaches he saw in nineteenth century continental writings, which had come through to the First World War, he believed had influenced the generals, such as the Allied Generalissimo, Marshal Foch. In his anthology of axioms by the commanders of world history entitled The Sword and the Pen (1978), Liddell Hart briefly cites Foch’s Principles of War, with the quotation: ‘No strategy can henceforth prevail over that which aims at ensuring tactical results, [namely] victory by fighting. A strategy paving the way to tactical decisions alone: this is the end we come to in following a study that has produced so many learned theories.’

This erroneous thinking, as Liddell Hart argued in his 1933 work The Ghost of Napoleon, had been the result of a misunderstanding stemming back to the Prussian Carl von Clausewitz. The Prussians had been shocked by the success of the Napoleonic methods of war, and Clausewitz had tried to understand its driving forces. Clausewitz’s conclusion was that the old strategy of manoeuvre was hopeless against the directness, simplicity, violence, and energy of the French Army. In the late nineteenth century, this interpretation had surprised French officers, who, while acknowledging Napoleon’s search for decisive battles, had made extensive use of ‘manoeuvre sur les derrieres’, a movement against the enemy’s rear. Drawing on the insights of fin de siècle French general and military historian Jean Colin, Liddell Hart seized upon these observations to reinforce his own arguments of how to avoid the authoritarian and Germanic direct approach which had caused so many casualties.

Liddell Hart’s preference was for surprise, manoeuvre, ‘the moral plane’ (that is, morale and psychology), and presenting multiple options for the enemy to induce hesitation, doubt, or the wrong choice of action. He also considered that, if time permitted, there should be an indirect approach using other levers of national power, including blockades (sanctions). He argued in his 1929 work:

Its application to the problem of normal warfare is conditioned by the factors of time, space, and force. [A blockade] is inherently slower to take effect than a strategy of dislocation. Hence, if national conditions make a quick issue imperative the latter appears preferable. But unless the end is sought by an indirect approach, the short cut is likely to prove slower, more costly, and more dangerous …

Liddell Hart had always been enamoured by air power, and, instead of laborious land campaigns, he considered how new technology such as long-range bombers could provide an alternative ‘strategic barrage’ in depth. In the 1940s, this interdiction strategy became an air force task, isolating enemy fighting formations at the front and depriving them of critical combat supplies and munitions.

At times, Liddell Hart could be guilty of an insistent and sometimes strident tone in his work. As one biographer noted: ‘Liddell Hart … tended to link this capacity for independent and critical judgement to inveigh against two of his bugbears: the mentally cramping effects of military professionalism and the tendency of British soldiers to acquiesce unduly in the hierarchy of seniority.’ But the clarity of Liddell Hart’s ideas made them appealing. When examining complex challenges, Liddell Hart could offer solutions.

Perhaps too little attention has been paid to Liddell Hart’s ideas on the psychological as well as the physical dislocation of the enemy. He offered a revision of the standard interpretation of Clausewitz, noting the subtle distinction that while Clausewitz had advocated ‘the employment of battle as a means to gain the object of war’, Liddell Hart noted that this battle should be brought about ‘under the most advantageous circumstances’ possible. The perfect strategy might be to win without fighting at all.

Liddell Hart was an advocate of a particular line of argument. He felt there was no shortage of determination and will in 1914-1918, but he felt that there had been an absence of critical thinking. However, his search for a general theory of strategy led him to elide over the specific conditions which had given rise to the direct approach and where it was necessary, such as the D-Day landings of 1944. As Professor Azar Gat has argued, he also tended to downplay the economic and social constraints of each era, in favour of a purely operational approach, attributing failure instead to an erroneous set of decisions. He had a tendency to focus on individual commanders, but he did not always appreciate the complex and competing demands that shaped decision-making.

There have been plenty of critics of Liddell Hart. Spenser Wilkinson, the Chichele Professor in the History of War at Oxford, disagreed with Liddell Hart’s ‘abuse’ of Clausewitz. It is hard to appreciate that Clausewitz was focused on understanding the nature of war, and Liddell Hart, as an author of military doctrine, was perhaps in pursuit of the applied aspects of the subject, and therefore found fault with the Clausewitzian emphasis on direct, focussed, and concentrated force. In a journal article written in response to Liddell Hart in 1927, Wilkinson argued that: ‘The war that aims at striking down the enemy by the destruction of his forces is that of a successful state’. Implying a criticism of ‘indirect approaches’, he went on: ‘The war that tries to limit its aims, and therefore its exertions, is that of the defeated.’ Wilkinson criticised Liddell Hart for arguing that the entire Western Front campaign had been a waste of resources, and claimed the imperative that had existed was to defend France by a concentration of forces in Western Europe. Yet Wilkinson was writing in a period when France was regarded as an essential pillar in Britain’s national defence. By contrast, Liddell Hart felt that Britain’s most successful strategy had always been to avoid the ‘continental commitment’ and focus instead on its maritime or air defences. In this sense, he was proven correct when France collapsed in 1940.

Professor Gat concludes that Liddell Hart was guilty, like Clausewitz in his own day, of pushing a line of argument too strongly, as a reaction to his immediate experiences: ‘The difference between them, of course, was only that one had stood at the dawn of the total war and called on his country for an all-out national effort …, whereas a century later the other witnessed the peaking of total war and preached restraint and a return to manoeuvre.’ It is a timely reminder that strategic concepts cannot be limited to singular solutions and each era will demand its own emphases.

Nevertheless, it is worth re-examining Liddell Hart as an advocate, not only of manoeuvrist warfare, but as a champion of a democratic approach to war itself. It is conducted with methods that make best use of psychological effects, mechanical means, and using all the levers of national power, rather than bluntly hammering at the adversary’s strongest points. Whatever the hard choices it presents, the strategic outcome must, above all, constitute a better state of peace, achieved at the lowest cost.