Absolutely. For half a century the leftists blocked people in northern California and southern Oregon from creating the State of Jefferson, giving every excuse under the Sun why secession is impossible. But California should be split up, into at least 3 but up to as many as 6 pieces. Even though it isn't apparent to many, the libs are active primarily in the large coastal cities while most of the land in California is conservative. Let them create a coastal state comprised of a piece immediately around San Francisco, another around Los Angeles. The rest stays put in the U.S.A., including the resource-rich regions that remain conservative.
Right about down the San Andreas fault. That could be the border.