This week, he taunted the city's highest-earning taxpayers with a letter informing them of another special tax awaiting them in the Big Apple.

As wealthy citizens flee the city, Mamdani strongly suggests that those who remain are going to get burned by his promised "warmth of collectivism." In doing so, he repeated a socialist myth about how the wealthiest taxpayers are not paying "their fair share."

Mamdani went on X to tell those with second homes in New York City worth more than $5 million that "you've got mail" and a "new pied-a-terre tax." He gleefully declared, "The best city in the world deserves the best parks, libraries, and schools in the world. That's only possible when we all pay our fair share."

The fair share myth is a virtual mantra among socialist and Democratic leaders, from Mamdani to Sen. Bernie Sanders (I-Vt.) to Rep. Ro Khanna (D-Calif.). In my book, "Rage and the Republic," I address the false claim that the wealthy are not "paying their fair share."

In fact, the top 10 percent already pay more taxes than the bottom 90 percent combined.

In 2023, the top 1 percent paid an estimated 38.4 percent of all federal individual income taxes. One can certainly raise the need for additional taxes to support public works, but it is simple demagoguery to claim that the wealthy do not pay their fair share when the top 10 percent pay an estimated 75 percent of federal income taxes. The U.S. income tax system is already the most progressive in the developed world, even before additional New York state and city taxes are added in.

The demonization of the wealthy is one of the oldest tactics of politicians seeking to empower themselves by harnessing mob rage.

Combined with pledges of free stuff under socialism, it creates a dangerous delusion among disgruntled citizens.

Another common fable has been repeated by socialists such as Darializa Avila Chevalier, the prison abolitionist who won a recent primary for Congress in New York. This radical, who once boasted how she wiped her hands on the American flag in lieu of a napkin, was pressed on whether there has ever been a "successful model of socialism anywhere in the world outside the U.S., in terms of both human rights and widespread economic justice."

She responded by citing Sweden and Norway, as other figures such as Sanders have done before her. Indeed, the claim of successful Scandinavian socialist systems is a sort of Marxist bedtime fairytale, told to children about a workers' paradise in quaint Nordic fishing villages.

But Sweden's experience only shows the limits of socialism even in a relatively small nation. Decades ago, after disastrous results to its economy, Sweden turned away from the very kind of socialist theories increasingly fashionable in the U.S. today.