This is a genuinely contested policy question where reasonable people disagree based on differing values and economic assumptions, so I'll lay out the main considerations rather than declare a "correct" answer.
Arguments for raising taxes on the wealthy
•Rising inequality: Wealth and income inequality in the U.S. have grown substantially since the 1980s, with top earners capturing a disproportionate share of income gains.
•Lower effective rates at the top: Due to preferential capital gains rates, deductions, and the ability to defer or avoid income recognition, many wealthy individuals pay a lower effective tax rate than their statutory bracket suggests—sometimes lower than middle-class earners pay. Warren Buffett famously highlighted this with his "secretary paid a higher rate than I did" observation.
•Revenue needs: Rising deficits and spending pressures (entitlements, defense, infrastructure) create a case for new revenue, and taxing those with the greatest ability to pay is one mechanism.
•Diminishing marginal utility: A dollar matters less to a billionaire than to a median earner, which is a classical argument for progressive taxation.
•Social/political stability: Some economists argue extreme inequality can undermine social cohesion, economic mobility, and democratic institutions.
Arguments against raising taxes on the wealthy
•Already highly progressive: The U.S. federal income tax system is already progressive—the top 1% pay a very large share of total federal income taxes relative to their share of income.
•Capital mobility and incentives: Critics argue higher rates on capital gains or high incomes could reduce investment, entrepreneurship, and savings, or drive capital/people to lower-tax jurisdictions.
•Behavioral responses: High earners often have more flexibility to restructure income, defer realization of gains, or relocate, meaning statutory rate increases don't always translate into proportional revenue increases.
•Double taxation concerns: Corporate profits are taxed, then dividends/capital gains are taxed again—some argue this already produces a high effective burden on investment income.
•Alternative approaches: Some argue that closing loopholes, improving enforcement, or taxing consumption/wealth differently would be more effective than simply raising marginal rates.
Where the debate tends to focus
The real policy fights aren't usually about the top marginal statutory rate alone, but about:
•Capital gains vs. ordinary income tax treatment
•Estate/inheritance taxes
•Wealth taxes (unrealized gains) vs. income taxes
•Loopholes like carried interest, stepped-up basis at death, and offshore structures
•Corporate tax rates and how they interact with shareholder taxation
My take
I don't think there's a single objectively "correct" rate—it depends on value judgments about fairness, growth tradeoffs, and the role of government, plus empirical uncertainties about behavioral responses that economists genuinely dispute. If you want, I can dig into specific proposals (e.g., Biden-era billionaire minimum tax proposals, wealth tax plans, or comparisons to other countries' systems) with current data to help you form a more specific view.