Breaking California into three states is no longer just a kooky idea being pushed by one rich guy. Now it’s a kooky idea that millions of Californians will face on the ballot in November.

The so-called Cal 3 proposition, written and funded by Silicon Valley venture capitalist Tim Draper, qualified last week for the ballot. While not quite as extreme as Draper’s earlier Six Californias proposal (which didn’t get enough signatures to qualify for the 2014 ballot), it surely seems like a long shot.

But so were “Brexit” and the election of Donald Trump — and look how those votes turned out. Voters are in a surly, disruptive mood these days, and there’s just no telling what foolish thing they’ll do next.

Under Draper’s proposal, the state would be divided into “California,” “Southern California” and “Northern California.” So, OK, here’s one big benefit we can think of: Right now, 39.5 million of us are represented by just two U.S. senators, meaning we have the same influence in that body as the 579,000 people in Wyoming. That’s unfair. Under this plan, there’d be six senators representing us.

But beyond that, the advantages are unclear. In an email, Draper told The Times that a breakup will “get us better infrastructure, better education and lower taxes.” But he offered no proof. Indeed, it is impossible to say what these still-conceptual new states would or wouldn’t do. Maybe they would support higher taxes or maybe they would cut school funding. How does Draper know?

What is guaranteed is tremendous upheaval and cost, at least in the short term, as three new governments are formed and then fight over how to split the state’s shared assets — courts, water resources, bureaucracies, infrastructure, etc. — and its debts. A report by the Legislative Analyst’s Office noted that all three states would be served by today’s State Water Project; that neither the prisons nor the public universities would be easily divided among the new states; and that income taxes would be concentrated in certain areas. You can bet that would be tied up in legal challenges for a good long time.

The last time part of a state calved off from another was during the Civil War, when West Virginia left Virginia. The subsequent litigation wasn’t resolved for half a century.

Of course, there’s no guarantee Congress would approve the establishment of the three states, even if the measure passed. Especially a Republican-controlled Congress (since it is not certain that any of the three could be relied upon to vote GOP).

Is this really the path Californians want to take? They’d better be really sure before voting yes. Before seeking new state birds and some new state flowers. Before requiring the U.S. to change its flag. Before doing away with the historical entity that is California — which, despite its size and its share of woes has done a pretty good job governing itself and setting a high standard for the country since it became a state in 1850.