Letting small slivers of a population amass as much wealth as they can grab might not be such a hot idea after all.

Two decades into the 21st century, a half-century into an America growing ever more unequal, the notion that some people can become too rich is finally seeping into our mainstream political discourse.

On the Internet, “every billionaire represents a policy failure” has become a popular meme, thanks to the wit and energy of activists around Rep. Alexandria Olivia-Cortez, the dynamic new member of Congress from New York.

On the campaign hustings, “two cents” has become the most popular chant at rallies for White House hopeful Elizabeth Warren. The senator from Massachusetts has proposed an annual 2 percent wealth tax on fortunes over $50 million and a 3 percent levy on fortunes over $1 billion.

Senator Bernie Sanders, meanwhile, has just upped the tax-the-rich ante. Sanders first detailed an annual wealth tax proposal in 2017. His latest iteration of the wealth tax idea, announced earlier this week, calls for a set of graduated annual rates that go all the way up to 8 percent on accumulations of private wealth over $10 billion.

“I don’t think,” Sanders told the New York Times at his new plan’s release, “that billionaires should exist.”

This sense — the conviction that grand concentrations of private wealth endanger our common well-being — is deepening all around the world, so much so that the every-billionaire-a-policy-failure perspective now has a philosophic label: limitarianism.

“In a nutshell,” notes the philosopher Ingrid Robeyns, a key figure in Fair Limits, a team of egalitarian-minded scholars at Utrecht University in the Netherlands, “economic limitarianism holds the view that no one should hold surplus money.”

And what rates as surplus? Wealth “over and above what one needs for a fully flourishing life.”