Friday is Valentine’s Day, the most saccharine holiday of the year. Ignoring it is noble social protest but, I can report from experience, risky domestic policy. Which is why, over the next two days, millions of consumers will be buying their significant others ridiculous red cards.

According to the industry’s trade group, some 145 million Valentine’s cards are sold in the U.S. every year. Those cards are ridiculous not just because of the sappy sayings on their covers. They’re ridiculous because, on a planet of seven billion people, it’s nuts to buy a piece of card stock, place it into a paper envelope, and give it to someone who (I love you, honey) will smile at it, stuff it in a sock drawer, and, almost certainly, never glance at it again. It’s even crazier to buy said piece of card stock, drive it to the post office, and have the U.S. mail truck it to an airport and then fly it to its destination.

Sure, you could criticize on environmental grounds all manner of small pleasures, such as eating burgers, or driving gasoline-powered cars, or drinking frostily refrigerated beer (all habits in which I happily engage). Yet sending a greeting card is worse as an example of personal carelessness, because its greener alternative is so painless and, indeed, so much more convenient. I don’t like veggie burgers, I can’t afford a Tesla, and I hate warm beer. But forsaking a paper greeting card for an emailed Valentine? I’m pretty sure I—as well as my family and you—could live with that.

Reason is no match for emotion, of course, so it’s no surprise that the dead-tree greeting-card industry continues to thrive. Sentimental pastimes die hard, and greeting cards aren’t Superfund sites. [...]

One piece of information the Greeting Card Association says it doesn’t have is the impact all those cards have on the environment. The pulp-and-paper industry is a major carbon-dioxide emitter and water user. But an Environmental Protection Agency spokeswoman said the EPA doesn’t track numbers for greeting cards.

Among the measures of a product’s environmental impact is its “carbon footprint”: the amount of carbon dioxide that’s emitted in the product’s manufacturing and use. But, as with Britannia Cards’ Amazon ad, measuring a product’s carbon footprint is dicey business, because the answer depends on what’s included in the calculation. Manufacturing? Manufacturing and transportation? Manufacturing, transportation and consumer use? The list of variables goes on and on.