When this column started in 2005, at the suggestion of then editor in chief Joan Hamilton, we expected it to last a few years. Readers, we figured, would run out of questions at some point, and it would fade gracefully away. But the inquiries kept coming, and by 2008 we even had enough to publish a book titled Hey Mr. Green.

While the column has undoubtedly helped readers reduce, reuse, recycle, and embrace efficiency, I’m concerned about its failure—and the failure of the environmental movement—to make all the radical and absolutely necessary changes to some of our most destructive behaviors and habits. It would be heartening, for example, if during those 15 years we saw the complete and total end of the disgusting purchases of millions of gigantic, gas-guzzling, energy-wasting pickups and SUVs. But that hasn’t happened. Total emissions from motor vehicles have actually increased in California, where full-size pickups outsold electric vehicles by a 3-to-1 margin in 2017. Meanwhile, fuel economy nationwide has only improved by a scant 6.1 miles per gallon since 2004. The auto industry continues to cynically, unscrupulously, and immorally hawk its big, inefficient pickups and SUVs—propelled by greed.

We also continue to waste vast amounts of electric power, pumping out huge quantities of carbon dioxide to make that power. What’s truly scandalous as well as puzzling is that the United States consumes almost twice as much electricity per capita as Germany, and more than twice as much per capita as Italy and Ireland. Instead of turning out the lights, turning down the heat, and shutting off the air conditioners, we continue to live in the fantasy of endless power and endless growth. It’s a fantasy that is leading us into catastrophes that we persist in denying.

On top of all this, we’re trashing our planet. One report makes the staggering prediction that if we keep tossing our junk out in the oceans, their waters will contain more debris than fish by 2050. Now China is refusing to accept our grossly contaminated recycled material, which has accelerated the closure of recycling facilities across our country. The average person tosses out nearly five pounds of garbage a day, with food waste and plastic accounting for more than 40 percent of the total. In 1960, by comparison, the average person dumped 2.68 pounds per day. Nearly 137 million tons still land in the dumps every year.

If you aren’t asking questions yet, you aren’t paying attention—a luxury we can no longer afford, as these dire statistics make clear. All the more reason to keep this column going, because who knows: Even if 15 years of answers didn’t change the world, another 15 might.

So take a few minutes to ask Ms. Green about what you can do to reduce, reuse, and recycle. She may not have all the answers you’re looking for—I certainly didn’t—but at least you’ll be asking the questions.