It got lost in the massive attention paid — with good reason — to Donald Trump’s triumphant return to the presidency, but a quiet revolution occurred in Los Angeles County.

Its voters approved a ballot measure to completely overhaul how the huge county, whose 10 million residents are greater than the populations of all but 10 states, is governed. After the 2030 census, the county’s Board of Supervisors will be expanded from five to nine members, hopefully making it more representative of the county’s incredible demographic diversity.

One could argue that the board should be even larger, perhaps 13 or even 15 members, to reduce each member’s constituency to a more manageable size. However, nine is certainly better than five.

The most startling aspect of the change is that the reform was placed on the ballot by a majority of the present board. It effectively reduces the clout that individual members have wielded, something that politicians are generally unwilling to do.

“People really want this change. They know it is time,” Supervisor Lindsey Horvath, chair of the board and co-author of the measure with Supervisor Janice Hahn, said on Tuesday after it became apparent that the measure would pass.

“Five supervisors for 10 million people? That doesn’t make sense,” Horvath added. “Even with the hardest working supervisor, people would like to see you more and pay more attention to their needs. It means we can do a lot better.”

While expanding the board received most attention prior to the election, another element of the overhaul will potentially have a greater political impact: the creation of an elected county executive, in effect a mayor of the county. The first election for the new position will occur in 2028.

Given the county’s size, it will hands down be the second most important political office in California and a very obvious stepping stone to the governorship, particularly since whoever wins the position is almost certain to be a Democrat.

With dozens of mayors, congressional members and state legislators — plus nine county supervisors — Los Angeles County will have no shortage of political figures vying for the powerful position.

Creating an elected county executive was the most controversial aspect of the proposal for the two board members who opposed placing the issue on the ballot. Supervisor Kathryn Barger, who voted against the measure with colleague Holly Mitchell, said it was wrong to have a position with no term limits.

“That will politicize our chief executive officer position. We need an executive that is nonpartisan and unbiased running the daily operations of the county, not another politician,” Barger said in a statement.

The quiet revolution that occurred in Los Angeles sharply contrasts with what didn’t occur 400 miles to the north in San Francisco. It’s a city and a county combined, California’s only such entity, governed by an elected mayor and an 11-member Board of Supervisors.

San Francisco voters ousted the incumbent mayor, London Breed, in favor of a wealthy philanthropist, Daniel Lurie, declaring that they wanted a change in governance. But at the same time, they rejected a ballot measure that would have reduced a bewildering array of 130 semi-independent commissions that wield much of the city government’s authority.

The interlocking powers of a mayor, supervisors and the commissions are widely cited as preventing San Francisco from addressing its most obvious civic issues, such as homelessness, crime and housing shortages.

A rival measure to study the commission system, which was placed on the ballot by the Board of Supervisors to thwart the more meaningful proposal, apparently passed.

Kudos to Los Angeles but a raspberry to San Francisco.

Dan Walters is one of most decorated and widely syndicated columnists in California history, authoring a column four times a week that offers his view and analysis of the state’s political, economic,...