B . H . Liddell Hart Sir Basil Henry Liddell Hart ( 31 October 1895 – 29 January 1970 ) , commonly known throughout most of his career as Captain B . H . Liddell Hart , was an English soldier , military historian and leading military theorist . He is credited with greatly influencing the development of armoured warfare . Life and career . Born in Paris , as the son of an English Methodist minister , Liddell Hart received his formal academic education at St Paul ' s School in London and at Corpus Christi College , Cambridge . His mother ' s side of the family , the Liddells , came from Liddellsdale , on the border with Scotland , and were associated with the South - Western Railway . The Harts were farmers from Gloucestershire and Herefordshire . As a child he was fascinated by aviation . On the outbreak of World War I in 1914 Liddell Hart volunteered to become an officer in the Kings Own Yorkshire Light Infantry . He fought on the Western Front . Liddell Hart ' s front line experience was relatively brief , confined to two short spells in the autumn and winter of 1915 , being sent home from the front after suffering concussive injuries from a shell burst . He was promoted to the rank of captain . He returned to the front for a third time in 1916 , in time to participate in the Battle of the Somme . He was hit three times without serious injury before being badly gassed and sent out of the line on July 18 , 1916 . His battalion was nearly wiped out on the first day of the offensive , a part of the 60 , 000 casualties suffered in the heaviest single day ' s loss in British history . The experiences he suffered on the Western Front profoundly affected him for the rest of his life . Transferred to be Adjutant to Volunteer units in Stoud and Cambridge , he spent a great deal of time training new units . During this time he wrote a several booklets on infantry drill and training , which came to the attention of General Sir Ivor Maxse . After the war he transferred to the Army Educational Corps and was given the opportunity to prepare a new edition of the Infantry Training Manual . In this manual Liddell Hart strove to instill the lessons of 1918 , and carried on a correspondence with Maxse , a commanding officer during the Battle of Hamel and the Battle of Amiens . These battles provided a practical demonstration of tactics for attacking an entrenched enemy . In April 1918 Liddell Hart married Jessie Stone , the daughter of J . J . Stone – who had been his assistant adjutant at Stroud – and their son Adrian was born in 1922 . Liddell Hart was placed on half - pay from 1924 . He later retired from the Army in 1927 . Two mild heart attacks in 1921 and 1922 , probably the long - term effects of his gassing , precluded his further advancement in the downsized post - war army . He spent the rest of his career as a theorist and writer . He worked as the Military Correspondent of the " Daily Telegraph " from 1925 to 1935 , and of " The Times " from 1935 to 1939 . In the mid to late twenties Liddell Hart wrote a series of histories of major military figures , through which he advanced his ideas that the frontal assault was a strategy that was bound to fail at great cost in lives . He argued that the tremendous losses Britain suffered in the Great War were due to her commanding officers not appreciating this fact of history . In the histories he wrote on Scipio Africanis Major ( 1926 ) , the Great Captains ( 1927 ) and Sherman ( 1929 ) he made the argument for maneuver warfare and taking the indirect approach to reach one ' s objectives . In the thirties Liddell Hart continued along this vein , and added the admonition that in the Great War Britain had moved away from her traditional strategy of using her naval superiority to attack her adversaries in places unexpected and at times of her choosing , and instead committed herself to a large army of conscripted men who fought on the Continent in direct confrontation with continental armies . The idea of keeping the British army off the continent thereby keeping British casualties low appealed to many people , among which was Neville Chamberlain . In a series of article for " The Times " from November 1935 to November 1936 , Liddell Hart argued that Britain ' s role in the next European war could be entrusted to the air force . He sought to avoid the complications involved from landing an army on the Continent . He believed that Britain should discard the idea of intervening in Europe with an army and inform the French that Britain would provide assistance , but from the air . These ideas influenced Chamberlain , then Chancellor , who argued in discussions of the Defence Policy and Requirements Committee for a strong air force rather than an army equipped for Continental warfare . When Chamberlain became Prime Minister in 1937 , Liddell Hart became a major intellectual influence behind British grand strategy of the late thirties . In May he prepared schemes for the reorganisation of the British Army for defence of the empire and delivered them to Sir Thomas Inskip , the Minister for the Co - Ordination of Defence . In June he gained an introduction to the Secretary of State for War , Leslie Hore - Belisha . Through July 1938 the two had an unofficial , close advisorial relationship . Liddell Hart provided Hore - Belisha with ideas that he would argue for in Cabinet or committees . On 20 October 1937 , Chamberlain wrote to Hore - Belisha : " I have been reading in " Europe in Arms " by Liddell Hart . If you have not already done so you might find it interesting to glance at this , especially the chapter on the “ Role of the British Army ” " . Hore - Belisha wrote in reply : " I immediately read the “ Role of the British Army ” in Liddell Hart ' s book . I am impressed by his general theories " . Liddell Hart , with Hore - Belisha , drafted a paper on ' The Role of the Army ' in November 1937 in which they argued that " home defence and empire defence were the primary responsibilities , and that the defence of other people ' s territory was , in comparison at least , secondary " . On 15 November Hore - Belisha wrote to Liddell Hart that " the Cabinet was moving towards the discontinuance of an Expeditionary Force for the Continent " and the next day wrote again to Liddell Hart , claiming Chamberlain was pleased by their paper on the role of the British Army and had requested from Liddell Hart a paper on ' The Reorientation of the Regular Army for Imperial Defence " . Behind Liddell Hart ' s policy contributions was the idea that the British decision in 1914 to directly intervene on the Continent with a great army was a mistake . He claimed that historically " the British way in warfare " was to leave Continental land battles to her allies , intervening only through naval power , with the army fighting the enemy away from its principal front in a " limited liability " . In September 1939 the War Cabinet completely reversed the Liddell Hart - Chamberlain policy . With Europe on the brink of war and Germany threatening an invasion of Poland , the cabinet chose instead to advocate a British and Imperial army of 55 divisions , for intervention on the Continent to come to the aid of Poland , Norway and France . Liddell Hart ' s influence greatly waned Shortly after World War II Liddell Hart interviewed or debriefed many of the highest - ranking German generals and published their accounts as " The Other Side of the Hill " ( UK Edition , 1948 ) and " The German Generals Talk " ( condensed US Edition , 1948 ) . Later Liddell Hart was able to convince the family of Erwin Rommel to allow him to edit the surviving papers of the German field marshal into a form which he published in 1953 as the pseudo - memoir , " The Rommel Papers " . The Queen made Liddell Hart a Knight Bachelor in the New Year Honours of 1966 . Theories . Theory of the Indirect Approach . Liddell Hart set out following World War I to address the causes of the war ' s high casualty rate . He arrived at a set of principles that he considered the basis of all good strategy . Liddell Hart believed the failure to act upon these principles which was the case for nearly all commanders in World War I led to the high casualty rate . He reduced this set of principles to a single phrase : " the indirect approach " . The indirect approach had two fundamental principles : In Liddell Hart ' s words , " In strategy the longest way round is often the shortest way there ; a direct approach to the object exhausts the attacker and hardens the resistance by compression , whereas an indirect approach loosens the defender ' s hold by upsetting his balance . " As a corollary he explained " The profoundest truth of war is that the issue of battle is usually decided in the minds of the opposing commanders , not in the bodies of their men . " Liddell Hart argued that success can be gained by keeping one ' s enemy uncertain about the situation and one ' s intentions . By delivering what he does not expect and has therefore not prepared for , he will be mentally defeated . Liddell Hart explained that one should not employ a rigid strategy revolving around powerful direct attacks nor fixed defensive positions . Instead , he preferred a more fluid " elastic defence " , where a mobile contingent can move as necessary in order to satisfy the conditions for the " indirect approach " . He later offered Erwin Rommel ' s Northern Africa campaign as a classic example of this theory . Liddell Hart ' s theory closely match what is currently referred to as Maneuver warfare , and has been advanced by John Boyd and his OODA loop Theory of combat and maneuver . He arrived at his conclusions after studying the great strategists of history ( especially Sun Tzu , Napoleon , and Belisarius ) and their victories . He believed the indirect approach formed the common element in the careers of the men he studied . He also advocated the indirect approach as a valid strategy in other fields of endeavour , such as business , romance , etc . As of 2009 , Liddell Hart ' s personal papers and library form the central collection in the Liddell Hart Centre for Military Archives at King ' s College London . Naveh controversy . Following the Second World War Liddell Hart pointed out that theories developed from those of J . F . C . Fuller and his own were adopted by Germany and used against the United Kingdom and its allies during World War II with the practice of what became known as Blitzkrieg warfare . This is supported by multiple sources , including Wilhelm Ritter von Thoma , one of the early developers of armoured warfare in Germany , who said : " The German tank officers closely followed the British ideas on armoured warfare , particularlarly those of Liddell Hart , also General Fuller ' s . " Two influential German officers with ties to the Nazi regime , Werner von Blomberg and Walther von Reichenau , read much of Liddell Hart ' s work and translated Liddell Hart ' s " The British Way in Warfare " into German . They circulated his ideas on mechanization throughout the Reichswehr . These ideas were reviewed and expanded upon by Guderian . In discussing the developments in armoured warfare in the European nations and Soviet Russia in his " Achtung - Panzer ! " , Guderian underscored the conflicts between the British military command and the British protagaonists for mechanization , specifically naming General Fuller , Martel and Liddell - Hart . This is further illustrated by Major General F . W . von Mellenthin , who in contrasting development of German armoured warfare techniques versus British development at the same time commented " In spite of warnings by Liddell Hart on the need for co - operation between tanks and guns , British theories of armoured warfare tended to swing in favor of the " all - tank " concept . " At one point the Chief of the General Staff , Ludwig Beck , a more conservative officer , is reported to have become so exasperated by Guderian and other younger officers expounding on the potential of armoured warfare that he said he wished he could have six months without having to hear Liddel Hart ' s name . In point of fact , in Guderian ' s " Achtung - Panzer ! " , written in 1937 , Guderian mentions Liddell - Hart by name , years before the two had ever met : In order to overcome the first of these disadvantages , the one related to unsupported armour , the protagonists of mechanization - General Fuller , Martel , Liddell Hart and others - advocated reinforcing the all tank units by infantry and artillery mounted on permanantly assigned armoured vehicles , together with mechanized engineers , and signals , support and supply elements . Despite ample access and evidence to the facts , Shimon Naveh , an Israeli military theorist , sought to undermine Liddell Hart in Israeli military circles by claiming that after the war Liddell Hart " created " the idea that Blitzkrieg was a military doctrine . Said Naveh , " It was the opposite of a doctrine . Blitzkrieg consisted of an avalanche of actions that were sorted out less by design and more by success . " Naveh advanced this argument as a means to attack the credibility of Liddell Hart , who had become highly influential among the Israeli military . Naveh claimed that by " manipulation and contrivance , Liddell Hart distorted the actual circumstances of the Blitzkrieg formation and obscured its origins . Through his indoctrinated idealization of an ostentatious concept he reinforced the myth of Blitzkrieg . By imposing , retrospectively , his own perceptions of mobile warfare upon the shallow concept of Blitzkrieg , he created a theoretical imbroglio that has taken 40 years to unravel " . Naveh claimed that in his letters to German generals Erich von Manstein and Guderian , as well as relatives and associates of Rommel , Liddell Hart " imposed his own fabricated version of Blitzkrieg on the latter and compelled him to proclaim it as original formula " . Naveh has a long history of attacking the intelligence and character of people he is in intellectual conflict with , including the General Staff of the Israel Defence Force . Of these men he claimed in an interview : " They are on the brink of illiteracy . The army ' s tragedy is that it is managed by battalion commanders who were good and generals who did not receive the tools to cope with their challenges . Halutz is not stupid , even Dudu Ben Bashat is not stupid , even though he is an idiot , and his successor , Major General Uri Marom , is a total bastard . " To buttress his attack upon Liddell Hart , Naveh sought to highlight the fact that the edition of Guderian ' s memoirs published in Germany differed from the one published in the United Kingdom in that Guderian neglected to mention the influence of the English theorists such as Fuller and Liddell Hart in the German - language versions . One example of the influence of these men on Guderian was the report on the Battle of Cambrai published by Fuller in 1920 , who at the time was a staff officer at the Royal Tank Corps . His findings and theories on armoured warfare were in fact read and later taken up by Guderian , who helped to formulate the basis of operations that was to become known as Blitzkrieg warfare . These tactics involved deep penetration of the armoured formations supported behind enemy lines by bomb - carrying aircraft . Dive bombers were the principle agents of delivery of high explosives in support of the forward units . The German version of Guderian ' s memoirs was published before the British copy . An explanation for the difference between the two translations can be found in the correspondence between the two men . In one letter to Guderian , Liddell Hart reminded the German general that he should provide him the credit he was due , offering " You might care to insert a remark that I emphasized the use of armoured forces for long - range operations against the opposing Army ' s communications , and also the proposed type of armoured division combining Panzer and Panzer - infantry units – and that these points particularly impressed you . " In his early writings on mechanized warfare Liddell Hart is well known to have proposed that infantry be carried along with the fast moving armoured formations . He described them as " tank marines " like the soldiers the Royal Navy carried with their ships . He proposed they be carried along in their own tracked vehicles and dismount to help take better defended positions that otherwise would hold up the armoured units . This contrasted with Fuller ' s ideas of a tank army , which put heavy emphasis on massed armoured formations . Liddell Hart foresaw the need for a combined arms force with mobile infantry and artillery , which was similar but not identical to the make up of the panzer divisions that Guderian created in Germany . Guderian corrected the oversight , and did as Liddell Hart requested . When Liddell Hart was questioned in 1968 about the oversight and difference between the English and German editions of Guderian ' s memoirs , he graciously replied merely : " There is nothing about the matter in my file of correspondence with Guderian himself except . . . that I thanked him . . . for what he said in that additional paragraph . " MI5 controversy . On 4 September 2006 , MI5 files were released which showed MI5 had suspicions that plans for the D - Day invasion had been leaked to Liddell Hart . Liddell Hart had prepared a treatise titled " Some Reflections on the Problems of Invading the Continent " , which he circulated amongst political and military figures . It is possible that Liddell Hart had correctly deduced a number of aspects of the upcoming Allied invasion , including the location of the landings . Liddell Hart stated his work was merely speculative . MI5 placed him under surveillance , intercepting his telephone calls and letters . Their conclusion was that Liddell Hart might have received the plans from General Sir Tim Pile , who was in command of anti - aircraft defences . No case was ever brought against Pile , supporting the notion that Liddell Hart had simply perceived the same problems and arrived at the same conclusions that the Allied general staff had .