Vice President Kamala Harris is championing higher taxes on wealthy Americans and corporations as part of her economic agenda. However, one of her proposed plans, known as the billionaire minimum tax, is facing challenges in gaining traction.

The billionaire minimum tax, which was also endorsed by President Joe Biden in his fiscal year 2025 budget, aims to impose a 25% minimum tax on total income, including unrealized gains, exceeding $100 million. This means that taxpayers with wealth above the threshold would have to report unrealized gains for each asset class annually, along with their original purchase price and market value.

According to a report by Henley & Partners, there were 10,660 people with at least $100 million in assets, living in the U.S. as of June 2023. Harris argues that it is unfair for the wealthiest individuals and corporations to pay lower tax rates than essential workers like teachers and nurses. She believes that implementing the billionaire minimum tax would ensure that everyone pays their fair share.

However, the proposal has encountered resistance both in Congress and among policy experts. Experts express concerns about the administrative challenges and potential legal disputes that may arise from implementing the tax. Erica York, a senior economist at the Tax Foundation's Center for Federal Tax Policy, argues that the plan moves in the opposite direction of sound tax policy. She cites liquidity concerns, possible gaming, and disputes with the IRS as some of the issues that may arise.

Additionally, the business community has also voiced its opposition to the billionaire minimum tax. Billionaire entrepreneur Mark Cuban doubts that the tax on unrealized gains would be implemented. He warns that such a tax could have adverse effects on the stock market.

Despite the support from Biden, the proposal has failed to gain sufficient political backing. Steve Rosenthal, a senior fellow at the Urban-Brookings Tax Policy Center, acknowledges the lack of support for the plan among politicians. He emphasizes that it is highly unlikely for the proposal to pass in its current form.

Further complicating matters, a Supreme Court ruling in June left questions about the constitutionality of wealth taxes, potentially further undermining the viability of the billionaire minimum tax.

As Vice President Harris continues to outline her economic agenda, the fate of the billionaire minimum tax remains uncertain. While many Americans support higher taxes on the wealthy, the challenges and critiques surrounding this particular proposal may hinder its implementation.