TL;DR
A giant drill just tunneled under a working shipping canal without holding up a single ship. A boring machine about the size of a four-story building finished the first tunnel bored under the Panama Canal on Oct. 26, carving a twin-track path for Panama City's Metro Line 3 as deep as 65 meters (213 feet) below sea level, while more than 4,500 sensors fed a data platform. In early November, a major Japanese builder said an AI system ran one of these giant machines on its own and steered more precisely than veteran operators, a company claim reported secondhand with no numbers attached. Put the two together and the picture is of tunnels dug faster, more safely and with fewer people underground, which is how cities get new subways and rail links sooner. Our odds on when an AI-run machine digs a real tunnel, and the timeline of breakthroughs that leads there, are below the line: subscribe to read them.
Below the line, for paid subscribers: The full story: where it stands, how we got here and what's dated next; our labeled speculation on what it adds up to; and every source.