The Marines plan to fire 155-millimeter artillery shells over a major freeway in Southern California on Saturday as part of a demonstration at Camp Pendleton.
Ms. Pelosi, 85, has not yet said whether she will run again. The challenge would be the latest example of the Democratic Party facing a push for generational change.
Gov. Gavin Newsom of California vetoed bills that would have provided tangible benefits to those descendants, though he approved a state agency to determine who qualifies for potential reparations.
Supporters of reparations for Black Californians rallied outside City Hall in San Francisco in 2023. The movement faces challenges as state leaders consider forms of compensation.