How Insane Are Republicans’ Tax Plans? Just Look at These Charts.

Marco Rubio’s tax cuts could cost almost as much as the entire Social Security program. 

Photo by Spencer Platt/Getty Images

The Republican primary campaign continues apace Tuesday night with another debate, this time on the Fox Business Network. Theoretically, the subject will once again be the economy, an issue the candidates have primarily dealt with by offering one titanic tax cut after another that would, of course, sink the federal budget unless they made equally massive spending reductions. If you’ve ever wondered what GOP policymaking might look like in a mathematically unconstrained conservative fantasia, these plans are it.

Take the proposals put forth by the two mainstream Republican favorites, Marco Rubio and Jeb Bush. So far, two notable think tanks, the left-leaning Citizens for Tax Justice and the conservatively inclined Tax Foundation, have scored their plans. They each arrive at vastly different cost estimates of the proposals, in part, from what I’ve been told, based on the different ways they handle changes to the corporate tax code and whether you factor in the pro-growth effect of lowering rates. But I’m not going to get into which group is more on target here, because they essentially point to the same conclusion: No matter how you run the math, these cuts are gargantuan. And the best way to see that is by comparing them with what the federal government currently spends on its major programs.

Let’s start with Rubio. Citizens for Tax Justice believes that his plan will ultimately cost the government $11.8 trillion over 10 years. That’s just slightly less than the roughly $12 trillion the entire Social Security program is expected to cost from 2016 through 2025, according to the Congressional Budget Office. It’s also more than the $9.1 trillion Medicare will require over the same period.

The Tax Foundation is slightly more optimistic. Based on its static scoring approach, which doesn’t take into account the feedback effects of economic growth, it thinks Rubio’s plan will cost about $6.1 trillion, which is a shade less than what the government expects to spend on defense from 2016 through 2025. Yes, that’s all defense. (Also worth noting: The group scored Rubio’s plan before he added one additional tax bracket for upper-middle classers, which should add to its expense.)

The Tax Foundation’s dynamic score, which does include the theoretical effects of economic growth, is slightly less grisly looking. Over a decade, Rubio’s plan would merely cost the combined equivalent of the Supplemental Nutrition Assistance Program (better known as food stamps), family support programs Temporary Assistance for Needy Families (better known as welfare as we now know it), unemployment insurance, Supplemental Security Income (which helps low-income Americans who are elderly, blind, or disabled), and the government’s child nutrition efforts. A trivial piece of the safety net, really.

And Bush? Well, according to CTJ his tax agenda would leave the government $7.1 trillion in the hole, which again is more than the entire defense budget.

Because Bush is becoming a bit of an afterthought, we’ll skip the Tax Foundation’s high-end estimate for the cost of his plan. But the dynamic version, economic growth included, would still come to $1.6 trillion, which is about on par with the entire Social Security Disability Insurance program. Barely anything.

Again, these are the tax plans on offer from the two leading mainstream GOP candidates for president. To make them work while eventually balancing the budget (as these men supposedly want to) would require excising massive chunks of the federal government in a manner that would undoubtedly fall hardest on the poor. Which is to say, a mainstream Republican in no way shape or form means a reasonable Republican.

Read more of Slate’s coverage of the GOP primary.