Nineteen U.S. billionaires are calling for a new wealth tax on their holdings to battle income inequality in the nation and boost public revenue to make America a better place.

“America has a moral, ethical and economic responsibility to tax our wealth more,” declared the billionaires in a letter Monday addressed to the “2020 Presidential Candidates.”

“Instituting a wealth tax is in the interest of our republic .... The next dollar of new tax revenue should come from the most financially fortunate, not from middle-income and lower-income Americans.”

Signers included liberal philanthropist and financier George Soros and his son Alexander Soros, Facebook co-founder Chris Hughes, heiress Abigail Disney and “Anonymous.”

They argue that the money raised — about $3 trillion over 10 years — could “substantially fund” investment in programs including clean energy, universal child care, infrastructure overhauls and tax relief for low-income families.

The letter calls proposals such as one floated by Sen. Elizabeth Warren (D-Mass.) a “moderate” tax on a “minuscule number of Americans” -- including them.

Warren has proposed a 2% marginal tax on assets beyond the first $50 million and a further 1% on assets worth more than $1 billion. She estimates that such a tax would affect just 75,000 families.

“Those of us signing this letter enjoy uncommon fortunes, but each of us wants to live in an America that solves the biggest challenges of our common future,” the letter notes.

The billionaires call a wealth tax “fair” and “patriotic.” It’s also a “powerful tool for solving our climate change crisis,” will “make America healthier,” and is good for the economy and democracy, the letter argues.

“Those of us in the richest one-tenth of the richest 1%” — who hold nearly as much wealth as the bottom 90% — “should be proud to pay a bit more of our fortune forward to America’s future,” the letter concludes.

“We’ll be fine. Taking on this tax is the least we can do to strengthen the country we love.”