In 1984, Margaret Thatcher privatised British Telcom for almost £4 billion, then the largest stock flotation in history. BT’s sale popularised privatisation as a key neoliberal policy in Britain and around the world, showing that governments could successfully sell their national infrastructures to the private sector.

This paper argues that BT’s history cannot simply be understood as an example of politicians transforming infrastructure, but instead shows how information technology has mediated political change. I begin by using institutional sociology and infrastructure studies to argue that political change, like technological change, is not a linear process from idea to action, but instead one that is shaped by infrastructure and institutions like British Telecom.

I show this through a history of how telecom engineers and managers computerized and digitalized BT’s network to protect its monopoly for Britain’s ‘second industrial revolution’, complicating BT’s move from public to private. I conclude by considering how, as infrastructure mediates radical political change, we can approach infrastructure ownership and development for today’s supposed ‘fourth industrial revolution’.