Hillary Clinton's Plan to Pay for Everything: New, Unspecified Taxes

Hillary Clinton's presidential campaign rolled out new policy proposal today: a $6,000 tax credit for home caregivers, designed to offset the cost families incur when caring for elderly relatives. Clinton also said she would like to boost Social Security benefits for some family caregivers who leave their jobs.

The campaign estimates that the price tag for the new benefit will run about $10 billion over the course of a decade. But as The Washington Examiner notes, Clinton hasn't detailed exactly how she'll pay for it, saying only that it would be paid for with tax hikes of some kind.

This isn't the first time that Clinton has proposed billions in new spending without providing all the details. There's also Clinton's higher-ed plan, which she's pitched as a way to make college more affordable (but which might have the opposite effect). Her campaign estimates that it would cost about $350 billion over a decade. The plan will be "fully paid for," she promises, "by limiting certain tax expenditures for high-income taxpayers." So she'd raise the tax bills on the wealthy, but, once again, she doesn't say how she'd do so. Clinton has also said that, somehow, her mandatory family leave plan should be paid for the by the wealthy, though it's not clear what the mechanism would be.

It's not that there's no possible way to raise the revenue to pay for these programs. But paying for all of them together becomes much harder, especially given that Clinton has boxed herself in to some extent by promising not to raise taxes on households earning less than $250,000, and in fact has called for tax cuts for the broad middle class.

That promise itself shows how difficult the politics of revenue-raising are right now: Clinton has ruled almost every household in the country off-limits.

Sure, there are still some pay-fors floating around in Washington, but the fact that they haven't been used yet (the Affordable Care Act, for one, used up a lot of them) suggests that we're beginning to scrape the bottom of the barrel. There just aren't that many obvious untapped revenue sources left, and the interest groups who are likely to be targeted have already mobilized heavily against them. 

Clinton's political calculation here is obvious: Promising to provide broad new benefits that few people have to pay for is always popular in politics. But it suggests how difficult it will be to settle on workable, politically plausible revenue raisers or other offsets to pay for new programs. It's easy for candidates to propose new programs and spending, and much harder to find ways to pay for them.