>If Waymo is successful, there are potentially massive impacts to the population of the US. Trucking is a major industry.

Certainly, but we don't know if it will be positive or negative. Some studies[0] show increases in human truck driver employment with long-haul being fully automated (plus the work seems nicer).

[0]https://www.theatlantic.com/technology/archive/2018/02/uber-...