Actually, as soon as they exit....the northern part of the state would succeed from the country of California, and prep the paperwork to re-enter the US as “Jefferson”. It’d be mostly conservative types voting. The country of California would only be from SF to San Diego. I would also have my doubts that San Diego would stay within the California country as well...probably ending up as it’s own country.
That is how West Virginia became a state.
It’s more probable CA splits into 3-5 different states long before it would be allowed to secede; which it never will be allowed to. Not a single chance on Gods green earth would the feds allow it. They might let the Bay Area which would include everything just North of San Jose to the Golden Gate bridge to about a half mile East of San Fran to secede but that would be about the extent of it and I seriously doubt the latter part.
That area I just mentioned is practically another country in both spirit and culture so it wouldn’t be like we would be giving up much. Oakland would still have the ports and the water would be a natural wall to keep them from moving in and out of the USA. A regular wall could be built at the SF city limits. About the only thing locals would miss is the access to the GG bridge and the International Airport on the South side. There are no longer any gun shops in SF so no big loss in that area unless Asian food is your thing in which case I bet some of those move out of the non USA zone before it happened. Many of them worked too hard to become American citizens to give it all up now for a bunch of crazy liberals.
San Diego is not the county you may remember at as. Far, far more liberal than it used to be. Used to live there, a brother still does. It has been subverted, I mean perverted into just another Calif city.
San Diego would risk losing access to the Navy Base there or to losing the base altogether. That is a very big incentive to stay with the USA though people there might not think about it until Secession becomes a real time possibility.
Hopefully a mini civil war would break out within the new country of California, wherein conservative Californians would slaughter all of the leftist vermin and rejoin the union. I can’t really think of a better outcome other than a spontaneous mass suicide of California leftists.