Waymo is expanding its operations to Washington, D.C. next year.This move is significant because D.C. presents unique challenges compared to the Sunbelt cities where Waymo has already launched.D.C. is densely populated, has complex infrastructure, and unpredictable weather, making it a more difficult environment for autonomous vehicles.Waymo's decision to operate in D.C. showcases their confidence in their technology and their ability to handle the challenges of the city.