Maxi pads and other feminine-hygiene products are subject to a so-called “tampon tax” in many states. (Chris Hondros/Getty Images)

Maybe this makes me a traitor to my sex, but I support the tampon tax.

Mostly because it’s not actually a tampon tax.

For those unaware, “tampon tax” is shorthand for the fact that menstrual products are subject to sales taxes in most states, even though other products considered necessities (such as food and medicine) are often exempted.

In recent months, this has spawned a legion of articles suggesting that squeamish, old, predominantly male politicians are punishing half of humanity for the crime of having a period. Some offer stories about poor women who say “tampon taxes” are cutting into money they desperately need for groceries or other bills.

The issue has gained steam on the left, partly because it fits neatly into both the “war on women” and “war on the poor” narratives. Protests have erupted across the United States and abroad; bills have been introduced in state legislatures around the country, and a change.org petition gathered more than 40,000 signatures. Activists have already logged wins in Canada and France.

Last week, even President Obama got drawn into the battle.

His interviewer, YouTube celebrity Ingrid Nilsen, posited that “pads, tampons and other menstrual products are taxed as luxury goods in 40 states.” She asked the president why.

A seemingly surprised Obama responded, “I have to tell you, I have no idea why states would tax these as luxury items. I suspect it’s because men were making the laws when those taxes were passed.”

But the premise of this question, and of the broader “tampon tax” debate, is wrong-headed.

First of all, it’s highly misleading to call the taxes that tampons are subject to “tampon taxes.” To my knowledge, no jurisdiction has a tampon-specific tax, as it might an alcohol or yacht tax.

Politicians didn’t one day decide that periods were gross and therefore ought to be made more expensive. Instead, when states and cities needed revenue, they passed general sales taxes — which happened to fall upon tampons along with countless other goods.

Then, every interest group on earth came out of the woodwork demanding a carve-out on the grounds that their product or service was a “necessity,” just as anti-“tampon tax” activists have recently done.

But what is a “necessity,” exactly?

It’s a pretty squishy term. Almost any product can be called necessary in modern times. And almost every product has.

In California, the state where a “tampon tax” repeal bill has gotten the most press, such tax-favored purchases include: candy and bottled water, school yearbooks, certain commemorative lapel pins, hot prepared foods sold to airlines, farm equipment, garment alterations and racehorse breeding stock.

The more things you exempt from sales taxes, of course, the higher the tax rates on other products have to rise to make up the lost revenue. That in turn increases the incentive for other interest groups to lobby for yet more exemptions, or find ways to disguise and recategorize their products to dodge taxes. (Is cold pizza a grocery item, and therefore a “necessity,” or a prepared food, and a luxury?) Which leads to more carve-outs for more “necessities.” Which leads to ever-higher tax rates.

This vicious cycle is one reason tax experts generally caution against creating product-specific exemptions to consumption taxes. Very low tax rates, over a broad base of items, cause fewer distortions, in both what people buy and how many resources get devoted to repackaging and marketing existing products.

Another reason to be skeptical about such exemptions is that they’re poorly targeted.

The most common rationale for exempting “necessities” — whether they be milk, Advil or, yes, tampons — is that such taxes especially hurt the poor. Low-income people, after all, spend a higher share of their incomes overall, and particularly more on “necessities,” however they’re construed.

But when you strip taxes from tampons or groceries, you relieve not just poor students and families from paying them. You’re also giving a break to billionaires.

A better way to address the regressivity of sales taxes is to just increase cash transfers to the poor — or to whichever group you think needs money the most. Maybe that’s women, since they are more likely than men to buy menstrual products, though I’m skeptical of the idea that government is obligated to address every difference in every demographic group’s consumption bundle.

Maybe it seems unfair that in so many states Twizzlers don’t get taxed while tampons do. But the solution isn’t to dole out yet more tax breaks but to end the ones we have and direct more public funds to people who actually need assistance.