By James Kwak
Incoming Treasury Secretary Steven Mnuchin promised a big tax cut for corporations and the “middle class,” but not for the rich. “Any tax cuts for the upper class will be offset by less deductions that pay for it,” he said on CNBC.
This is impossible.
The tax cutting mantra comes in two forms. The more extreme one claims that reducing the overall tax burden on the rich will turbocharge the economy because they will save more, increasing investment, and will also work more, starting companies and doing all those other wonderful things that rich people do. The less extreme version is that we should lower tax rates to reduce distortions in the tax code, but we can maintain the current level of taxes paid by the rich by eliminating those famous “loopholes and deductions.” Donald Trump the candidate stuck with the former: his tax proposal, as scored by the Tax Policy Center, gave 47% of its total tax cuts to the top 1%, who also enjoyed by far the largest reduction in their average tax rate.
Mnuchin’s comment implies that he favors the latter version: lowering rates but making it up by “broadening the base.” This math might work for the merely rich—say, families making $200,000–400,000 per year. Take away the mortgage interest tax deduction, the deduction for retirement plan contributions, and the exclusion for employer-provided health care—which together can easily shield $50–75,000 in income—and you could probably fund several percentage points of rate decreases. (Of course, it would be politically impossible to completely eliminate those tax breaks, but that’s another story.)
The Baseline Scenario 