Tim Harford:

Internal politics soon asserted itself. A case study co-authored by Henderson describes the PC division as “smothered by support from the parent company”. Eventually, the IBM PC business was sold off to a Chinese company, Lenovo. What had flummoxed IBM was not the pace of technological change — it had long coped with that — but the fact that its old organisational structures had ceased to be an advantage.

Rather than talk of radical or disruptive innovations, Henderson and Clark used the term “architectural innovation”.

“An architectural innovation is an innovation that changes the relationship between the pieces of the problem,” Henderson tells me. “It can be hard to perceive, because many of the pieces remain the same. But they fit together differently.”

An architectural innovation challenges an old organisation because it demands that the organisation remake itself. And who wants to do that?

The armies of the late 19th century were organised — as armies had long been — around cavalry and infantry. Cavalry units offered mobility. Infantry offered strength in numbers and the ability to dig in defensively.

Three technologies emerged to define the first world war: artillery, barbed wire and the machine gun. They profoundly shaped the battlefield, but also slipped easily into the existing decision-making structures. Barbed wire and machine guns were used to reinforce infantry positions. Artillery could support either cavalry or infantry from a distance.

Tanks, however, were different. In some ways they were like cavalry, since their strength lay partly in their ability to move quickly. In other ways, they fitted with the infantry, fighting alongside foot soldiers. Or perhaps tanks were a new kind of military capability entirely; this was the view taken by J F C Fuller.

These discussions might seem philosophical — but in the light of Henderson’s ideas, they are intensely practical. “You have to find an organisation that will accept the new bit of technology,” says Andrew Mackay. Mackay runs an advisory firm, Complexas, but was also the commander of British and coalition forces in Helmand, Afghanistan, in 2008. “The organisational question is deeply unsexy, but it’s fundamental.”