“News in this country flows east to west, always has and always will, but political and cultural movements flow west to east,” said Averell Smith, a longtime Democratic strategist who worked in campaigns nationwide and grew up in San Francisco, where his father was the district attorney.

The different responses that have been on display during these difficult weeks also illustrate the cultural, political and philosophical ways in which California, Washington and Oregon are distinct from the rest of the nation, a trend that has only accelerated since President Trump was sworn in.

California and Mr. Newsom have been under fire for delays in developing tests for the virus; New York has far outpaced California in testing potential victims. But the six Bay Area counties, including San Francisco, announced shelter in place orders on March 16. Mayor Eric Garcetti issued a stay at home order for the city of Los Angeles on March 19. Later that day, Mr. Newsom issued a statewide stay-at-home order.

Mr. Cuomo, who earlier that week had resisted a call from Mayor Bill de Blasio of New York to issue a stay-at-home order, followed a day later for New York — but that not take effect until March 22. Epidemiologists said that given the speed with which the virus spread and the density of parts of New York City, that delay was troubling.

“I remember seeing Governor Cuomo on TV making comments about not wanting to take away people’s civil liberties,” said London Breed, the mayor of San Francisco. “I understand that, I totally understand that, But I don’t think that’s what we were doing. I know the information I had. It showed me the best-case and worst-case scenarios and provided the guidance to avoid the worst-case scenarios.”

“I think we’re going to look back and see that issuing this order had a tremendous impact on the number of people who have been infected, and also the number of people who died,” she said.

[Sign up for California Today, our daily newsletter about the Golden State.]

The West Coast is different than the East Coast in many ways.