Radios and the use of aircraft allowed for easy communication between Units spread across hundreds, if not thousands meters, connecting commanders to their units almost instantly. The development of the internal combustion engine led to the use of tracked and wheeled vehicles as battlefield transports and weapons platforms (ie tanks, armoured cars, Self-Propelled Artillery) on the battlefield.

Both of these were the products of the First World War, and developed into their own in the twenties and thirties. Advances in communications, artillery and aircraft, the development of the tank, and the establishment of modern all-arms tactics and doctrine, notably among the Anglo-French armies, but also including German 'stosstruppen' tactics, created a fluid, mobile battlefield on the Western Front in 1918, which had been moving towards this in 1917, with the Germans moving away from static trench-based defences and the Allied developments of 'Bite-and-Hold' methods.

Even still, 'set piece battles' in the modern sense, two armies facing each other across hundreds of kilometers, one moving against the other with artillery, infantry and armour working together, gradually forcing the enemy back or destroying him through attrition, were fairly common. Bernard Montgomery demonstrated his grasp of these methods in his victory at Second El Alamein, essentially perfecting the set-piece methods of the allied generals of 1917-18; which is incredibly ironic, considering he claimed in his post-war memoirs that the Generals of the Western Front taught him "what NOT to do."

Peter Hart, "Great War: A Combat History of the First World War"; William Philpot, "War of Attrition: Fighting the First World War" & "Three Armies on the Somme"; Richard Holmes, "Tommy"; Gary Sheffield, "Forgotten Victory" & "The Chief: Field Marshal Douglas Haig"