The basic idea behind the “mulligan” ­– you flub a shot, you get to take the shot again — may be golf’s most endearing contribution to world civilization.

In our real-world economy, unfortunately, we don’t get to take mulligans. We certainly could use one. Here in the United States, a new report from the nonpartisan Congressional Budget Office makes depressingly clear, we’ve essentially flubbed the last three decades.

Over that span of time, America’s total family wealth has more than doubled, to $67 trillion. But most average American families haven’t seen a nickel of that gain.

A new report out of the UK is reviving interest in the notion of a capital levy.

In fact, the typical American family headed by someone under age 65 actually lost wealth between 1989 and 2013, after adjusting for inflation.

Families in the upper reaches of the American economy, by contrast, have done just swell. Families in the top 10 percent, the Congressional Budget Office calculates, have seen their net worths increase an average 153 percent.

Families in the top 1 percent have done the best of all. Their overall share of the nation’s wealth, the new CBO report finds, has jumped from 31 percent in 1989 to 37 percent in 2013.

These figures may understate how unequal the U.S. economy has become. Other reputable statistical methodologies, the CBO report acknowledges, put the current top 1 percent share of the nation’s wealth as high as 42 percent.

None of this substantial transfer of wealth — to America’s economic summit — had to happen. Policy makers chose to make to happen, by changing the rules on everything from taxes and trade to labor law and business regulation.

And now the wealthy have huge chunks of the new wealth these rule changes have generated sitting in stocks, derivatives, and other financial assets that are, in turn, generating still more new wealth for America’s richest.

Wealth, in other words, is begetting more wealth for the wealthy. Society is becoming ever more unequal. If only we could take a mulligan — on our past wealth-concentrating quarter-century.

Well, maybe we can. At least, that’s what analysts like Britain’s Nick Donovan believe. Donovan recently authored a proposal for a one-time tax on the wealth of the UK’s wealthiest.

Among all the world’s major industrial nations, the UK currently comes the closest to matching the concentration of wealth that Americans have experienced since the 1980s. A “one-off levy” on the wealth of the wealthy, Donovan argues in a new report for Britain’s Fabian Society, could begin to undo that concentration.

Annual taxes on the wealth of the wealthy do already exist in several European nations. But annual wealth taxes haven’t yielded much revenue, mainly because the tax rate they impose typically runs only a fraction of 1 percent, and over time, Donovan notes, “political pressure tends to result in more assets being exempted and yields reducing still further.”

The one-time levy Donovan supports would carry a much higher tax rate and target what he calls “passive wealth,” the fortunes the wealthy have sitting in financial assets that their portfolio managers, private bankers, and lawyers manage for them.

One-time taxes on wealth, Donovan adds, have a “long pedigree.” The idea goes back to the ancient Greeks. In modern times, Germany implemented a one-time wealth tax — a “capital levy” — after World War II, and German support for another such levy has been growing over the past few years.

The idea of a one-time wealth tax has even had some high-profile backing in the United States — from the unlikeliest of sources. In 1999, Donald Trump called for a one-time “net worth tax” of 14.5 percent. A levy on individual and trust fund wealth over $10 million, Trump said at the time, would raise $5.7 trillion from the nation’s top 1 percent.

This wealth tax idea has totally disappeared from Trump’s current line-up of tax proposals. The latest tax planfor his 2016 Presidential campaign significantly reduces taxes on the top 1 percent — and would save, if enacted, his own family dynasty over $7.1 billion on federal estate taxes alone.

In the UK, Donovan’s wealth tax proposal has a strong supporter in Parliament. No such champion for a one-time wealth tax has yet emerged in Congress. If more Americans contemplate the latest Congressional Budget Office numbers, that could well change.