Unsustainably lavish pension and union deals ... rosy-scenario budget assumptions ... dwindling tax revenues stemming from sustained, historically high unemployment ... an aging population moving in ever-larger numbers into retirement. Those and other factors have driven another government into insolvency.

No, not the Greek government. And not the U.S. government — at least not yet.

In this instructive case, it was the government of San Bernadino, Calif., that filed for bankruptcy Tuesday. The drastic move, described by local officials as their last resort, continued an alarming trend in our most populous state.

Stockton, home to nearly 300,000 people, became the largest U.S. city to ever take the bankruptcy route on June 28. San Bernadino isn’t a small town either, with roughly 200,000 residents.

And while the population of also-broke Mammoth Lakes is only 8,000 or so, its inability to fulfill its financial obligations — forcing a July 2 bankruptcy filing — also reflects a mammoth problem facing municipal governments throughout California.

The state government is also awash in red ink, though a $16 billion budget shortfall projected earlier this year has been reduced to less than $10 billion.

As for San Bernadino’s insurmountable $46 million deficit, Wednesday’s Los Angeles Times reported that it “has been years in the making, compounded by the nation’s crushing recession and exacerbated by escalating pension costs, lucrative labor agreements, Sacramento’s raid on redevelopment funds and a city reserve that is tapped out.”

Adding to the burden, according to the city attorney, was the obscuring of the red-ink flood by falsifed financial documents given to the mayor and city council for 13 of the past 16 years.

It’s reassuring to know that thanks in large part to responsible leadership and sound fiscal practices, South Carolina municipalities are not experiencing the balance-sheet nightmares now haunting many California communities.

But it would be naive to imagine that the spreading affliction of American cities going broke is confined to California.

From Tuesday’s New York Times: “When the city of Scranton, Pa., found itself down to its last $5,000 in the bank last week, its Democratic mayor took a highly unusual step: he unilaterally cut the pay of city workers — including police officers, firefighters and even himself — to the minimum wage, just $7.25 an hour. Now the city’s unions are fighting for their promised pay in court.”

The key word in the previous sentence is “promised.” For too many governments in California and elsewhere, steep bills are now coming due — and they’ll keep coming — for financial promises that can’t be kept.

Just as Europeans have been arguing for the last two and half years about whether and how to bail out Greece, Americans could soon be arguing about whether and how to bail out California.

And the longer Americans keep delaying the hard choices needed to live within our means, the greater the risk of our nation going the down-and-out way of the no-longer-so Golden State.