It is actually: knowledge, intelligence, communication, and a form of secrecy.

A single intelligent person is bounded in its reach by the network of people they can form around them and by which important/powerful people they can influence either directly or indirectly.

The idea behind the AI breakout is that it’s intelligence is maybe limited, but it will be able to quickly spread and covertly bring many devices into its influence. We already have the tools for formally letting agents talk to each other so it can also create a topology of agents that consists of cells where need to know is applied etc.

There are many forms of power some more obvious, say nation leaders, versus more silent powers such as career politicians or wealthy families or people controlling the media and thence the flow of information.