I think you're right about all that, and that it's even worse than that.
With what military would the new California defend itself? What would stop the United States-sans-California from immediately annexing California as a territory, putting things in the exact same situation as now, but without any of the self-determination afforded by being a state? I don't know how realistic that is, but it's hard to reason about the hypothetical world where this proposal succeeds, and it seems like a serious risk.
Escape is not the solution. All it does is leave the world's most powerful country in the control of the people you disagreed so strongly with that you wanted to leave.
With what military would the new California defend itself? What would stop the United States-sans-California from immediately annexing California as a territory, putting things in the exact same situation as now, but without any of the self-determination afforded by being a state? I don't know how realistic that is, but it's hard to reason about the hypothetical world where this proposal succeeds, and it seems like a serious risk.
Escape is not the solution. All it does is leave the world's most powerful country in the control of the people you disagreed so strongly with that you wanted to leave.