The states which became the Confederacy had been paying nearly 3/4ths of all the federal expenses. It is the 20 Million Northerners who weren't paying their fair share.
This is the opposite problem from what California has.
So I assume that is your left-handed way of admitting that the Southern states never made an offer to pay for anything? So why should California? I'm sure they can invent all sorts of claims on how they paid more than their fair share for years just as easily as you can. And can therefore walk away without any obligations at all.
No, statistics show that California not only pays the most taxes of any US state, but also one of the highest taxes per capita.
Among the reasons are California's hugely profitable hi-tech and entertainment industries.
Back in 1860 the correct number is one half of US exports came from Deep South secession states.
The other half came from Union states, including gold & silver from California & Nevada.
Deep South cotton & rice were produced by 3.5 million slaves who both heard about and appreciated the election of abolitionist "Ape" Lincoln and his Black Republicans.