You know American politics is fraying when California liberals are plotting how to secede from the Union, Berkeley is the new poster child for suppressing free speech on college campuses, and fascist gangs dressed in black go around destroying property and physically assaulting people who hold differing political views — all while calling themselves “anti-fascists.”

It’s like National Opposite Day. What the county is lacking, among other things, is the historical knowledge that might temper such political passions. The California secession talk is a prime example.

It’s unclear how many California schoolchildren are still taught about Aaron Burr’s fateful duel with Alexander Hamilton. More than were taught a generation ago, I suspect, thanks to a certain Puerto Rican genius and his wildly successful Broadway musical. But I’d wager money that not one in a thousand Californians can tell you about the 1859 duel between David S. Terry, chief justice of the state Supreme Court, and David Broderick, one of the first U.S. senators sent to Washington from the Golden State.

Sen. Broderick did not die in vain. His death galvanized opposition to the pro-slavery “Chivalry” wing of California’s Democratic Party. The “Chivs” were transplanted Southerners who were maneuvering to either legalize slavery in California or divide the state in two, North from South. Fantasies about partitioning California are a recurring theme, pre-dating the state’s admission to the Union as a free state in 1850. But compromise isn’t what we do anymore. The latest fad, “Calexit,” involves exiting the USA altogether. Singularly ill-conceived, it’s generating a nationwide buzz. What the rest of the country wants to know is: Will they do it? Can they do it? What would happen then?

Signatures are being gathered by a political organization with a typically Orwellian name: “Yes California.” (I assume the domain name “Screw Abe Lincoln” was taken already.) Nearly 600,000 valid signatures are required to get the measure on the 2019 ballot; Yes California says it has some 7,000 volunteers out gathering them now.

Would Calexit pass in a referendum?

It’s certainly possible. Make no mistake, this push is fueled by antipathy to Donald Trump, who lost California to Hillary Clinton California by 4.3 million votes. If “Yes California” officials can turn it into a referendum on Trump’s presidency, why not?

Moreover, this is a place where citizens voted to have two separate property tax systems depending on when you bought your house, to deny public schooling to the children of undocumented immigrants, and make it illegal for gays and lesbians to marry. The point being: you never know.

Is California allowed to leave?

The short answer, in case you’re one of those people whom Jay Leno liked to interview on his “Jaywalking” segment and never heard of the Civil War, is “no.”

But what if a state wanted to leave, and asked for permission much more nicely than South Carolina did in 1861 by firing artillery into a U.S. Army installation in Charleston Harbor? Four years after the Civil War ended, the U.S. Supreme Court ruled on the constitutionality of secession in a case called Texas v. White.

Writing for a 5-3 majority, Chief Justice Salmon Chase ruled that the Constitution “in all its provisions, looks to an indestructible Union.” You’d need a new Supreme Court precedent, permission from the other 49 states, and probably a constitutional amendment. In other words, it could happen when hell freezes over. But we’re living in times of grave concerns about climate change, so maybe this could happen before the devil is handing out ice cream cones to his recent arrivals. But then what?

What would Calexit bring?

Here’s the fun part, but only if you’re a conservative with a fiendish sense of humor. First, huge population increases. These new pilgrims would range from native Californians (I presume we’d have dual citizenship) flocking back to their homeland to waves of anti-Trumpers desiring to live with like-minded sophisticates. Yes, California would take these ideological refugees. It’s already full of “Sanctuary Cities” and, under Calexit, would be a virtual sanctuary state, a magnet for tens of millions of immigrants from foreign countries, including, presumably all those from President Trump’s infamous seven Muslim-majority “countries of concern” who could afford the air fare.

The Golden State would soon turn Golden Brown, too, and that isn’t a reference to California President-in-waiting Jerry Brown. I’m talking water rights, specifically the Colorado River. Already, a Denver utility is planning a huge expansion of Gross Reservoir in Boulder County. Wyoming has similar plans afoot, too, in a Colorado River tributary and officials in Nevada and Arizona covet more Colorado River water, too.

Under Calexit, the interstate compact that apportions Colorado River water would be the subject of treaty negotiations between two sovereign nations, one of which has the water, and the other which wants it. Keeping the lush Imperial Valley from turning into another Death Valley could cost trillions.

All those new people — you’d be looking at a population of 100 million — would need drinking water, which would necessitate water desalination plants, fueled most likely by the nuclear power plants the state is now busily decommissioning.

For Republicans, the best news would be the ripple effects in politics. The Senate would immediately become two Democrats lighter and Trump’s re-election chances would suddenly seem brighter. Future GOP nominees wouldn’t have to worry about California’s dependable bloc of 55 Democratic votes in the Electoral College. Yes, California, they’d say, by all means do secede.

Carl M. Cannon is executive editor and Washington Bureau chief of RealClearPolitics.