IN THE CONVENTIONAL VIEW of American politics, Joe Biden is a moderate, while Elizabeth Warren and Bernie Sanders are on the left, and Donald Trump is on the right.

This conventional view is rubbish. The most powerful force in American politics today is antiestablishment fury at a rigged system. There are no longer moderates. There’s no longer a center. Today’s great divide is not between left and right. It’s between democracy and oligarchy.

Four decades ago, when America had a large and growing middle class, the left wanted stronger social safety nets and more public investment in schools, roads and research. The right sought greater reliance on the free market.

In those days, a general election was like a competition between two hot dog vendors on a long boardwalk extending from the left to the right. Each had to move to the middle to maximize sales. If one strayed too far left or right, the other would move beside him and take all sales from the rest of the boardwalk.

This type of American politics is now obsolete. As wealth and power have moved to the top and the middle class has shrunk, more Americans have joined the ranks of the working class and poor. Most Americans, regardless of whether they were once on the left or right, have become politically disempowered and economically insecure. Nowadays, it’s the boardwalk vs. private jets on their way to the Hamptons.

As Rahm Emanuel, Barack Obama’s chief of staff and the former mayor of Chicago, Ill., told The New York Times in July “This is really the crack-up. Usually fights are Democrats vs. Republicans, one end of Pennsylvania vs. the other or the left vs. the right. Today’s squabbles are internal between the establishment vs. the people that are storming the barricades.”

In 2016, Trump harnessed many of these frustrations, as did Bernie Sanders. If anything, the frustrations today are larger than they were then. Corporate profits are higher, as is CEO pay. Markets are more concentrated. The three richest Americans now have more wealth than the bottom half of the population put together. Yet, most people’s pay has gone nowhere and they have even less job security.

Meanwhile, Washington has become even swampier. Big corporations, Wall Street and billionaires have entrenched their power. Trump has given them all the tax cuts, regulatory rollbacks and subsidies they’ve wanted.

Why doesn’t the rest of America rise up in protest against Trump’s virulent attacks on American democracy? Because American democracy was dysfunctional even before Trump ran for president. The moneyed interests had already taken over much of it. It’s hard for many Americans to get very excited about returning to the widening inequalities and growing corruption of the decades before Trump; which partly explains why Joe Biden is foundering.

At the same time, Trump and his propagandists at Fox News have channeled working-class rage at the establishment into fears of imaginary threats such as immigrants, socialists and a “deep state.”

But a large majority of Americans — right and left, Republican as well as Democrat — could get excited about moving toward a real democracy and an economy that works for the many. This is why the oligarchy is so worried about Warren’s rise to front-runner status in some polls.

Politico reported that Democratic-leaning executives on Wall Street, in Silicon Valley and across the corporate world are watching Warren with an increasing panic. “Ninety-seven percent of the people I know in my world are really, really fearful of her,” billionaire Michael Novogratz told Bloomberg.

These Democratic oligarchs hope Biden or perhaps Pete Buttigieg or Amy Klobuchar can still take Warren out. In just the third quarter, Buttigieg raised around $25,000 from executives at finance firms such as Goldman Sachs, Morgan Stanley and JPMorgan along with hedge fund giants such as Bridgewater, Renaissance Technologies and Elliott Management. Buttigieg raised another $150,000 from donors who described their occupation as investor.

If Biden implodes and neither Buttigieg nor Klobuchar takes the lead away from Warren, Wall Street and corporate Democrats hope former New York City, N.Y., Mayor Michael Bloomberg will make a late entrance in the Democratic race.

It won’t work. The stark reality is that Democrats cannot defeat Trump’s authoritarian populism with an establishment candidate who fronts for the oligarchy. The only way Democrats can win is with an agenda of fundamental systemic reform such as provided by Warren and Sanders.

Unless Democrats stand squarely on the side of democracy against oligarchy, they risk that Election Day, too many Americans will either stand with Trump or stay home.

Robert Reich’s latest book is “The Common Good” and his newest documentary is “Saving Capitalism.”