Our friends on the left like to remind us that, “When the Founding Fathers talked about the right to bear arms, they meant Brown Bess muskets—not AR-15s.” And speaking as a certified gun nut, they have a point. 

We have no idea what the Founders would have said about high-capacity magazines. Modern rifles can carry up to 100 rounds. Meanwhile, just 450 Americans died at the Battle of Bunker Hill. The men who drafted the Second Amendment couldn’t have imagined having the power to kill at this scale.

Yet here’s the thing. Opponents of gun control don’t say that high-capacity magazines are a great blessing to the human race. We say, “If you make guns illegal, only criminals will have guns.” The Bad Guys are going to get their hands on these weapons, whether we like it or not. The question is whether the Good Guys will be able to defend themselves.

Advances in technology mean we have to rethink the laws around that technology.

That is perfectly fair. But what if laws aren’t strong enough? What if the government can’t contain the harmful effects of new technology? And so-called “assault” rifles are only the beginning. Today, we also have to reckon with the homemade firearm.

On July 8, former Japanese prime minister Shinzo Abe was shot and killed at a political rally. His assassin, Tetsuya Yamagami, fits the profile of an American mass shooter. He’s a loner from a troubled family with no ambition in life. But there is a key difference. American shooters usually get their guns from their parents or buy them from a gun fair. In Japan, handguns are totally illegal. So, Mr. Yamagami made his own. 

Homemade handguns are virtually impossible to regulate. The weapon used to kill Mr. Abe was built with a lithium battery, a couple of pipes, a block of wood, and some duct tape. Even in the United States, where factory-made handguns are widely available, gun enthusiasts are using 3D printers to fabricate their own. They just like them. It’s part of the DIY trend, like baking your own sourdough or brewing your own beer.

For those who don’t know, 3D printers are like the Replicators from Star Trek. They can be used to make everything from pizza to prosthetic limbs. Some companies now use them to create “3D selfies”: personalized statuettes, like the figurines you put on top of wedding cakes. They have the potential to improve the lot of our fellow man. They also seem like a lot of fun.

This leaves our governments in a real pickle. Do they make 3D printers illegal in order to prevent 3D-printed gun crimes? Or do they let the people decide how they’ll use this technology and punish those who misuse it? 

Of course, there is a third option. They could pass laws making it illegal to fabricate weapons using 3D printers. Yet this would be a purely symbolic gesture. It wouldn’t prevent crime; it will only allow district attorneys to tack on extra charges once a major felony has been committed. Mr. Yamagami will have to serve five years for possession of an illegal firearm on top of his life sentence for first-degree murder. 

American law will definitely choose option three. We always do. On the one hand, we refuse to hinder the progress of Science. (Imagine what future historians would say about us. “Luddites!” “Reactionaries!”) On the other, we don’t trust our countrymen to use the blessings of Science responsibly. So, we split the baby. We make life difficult for law-abiding citizens while basically doing nothing to prevent criminals from plying their trade.

And as these technologies become more advanced, even our nominal attempts at regulation become more and more absurd. After every mass shooting, our liberal friends insist, “We have to do something!”—or, better yet, “We can’t do nothing!” But what if there’s nothing we can do? 

This is the prevailing mood of the modern world: a feeling of total helplessness, which we try to allay through lots of useless activity. 

It all began with the invention of the atom bomb. Except for a few American generals and Nazi scientists, nobody on the planet actually wanted the A-bomb. We didn’t give our government permission to build it. We didn’t give them permission to use it, either. We’ve carried our guilt over Hiroshima and Nagasaki for eighty years. We lived in the bomb’s long shadow during the Cold War. Even today, when North Korea rattles its saber or Russia invades one of its neighbors, our thoughts turn to nuclear holocaust.

Man invented the bomb. Yet even in its cradle it was the bomb that called the shots.

Or take a more mundane example: smartphones. According to a recent poll, over half of Americans say they use their smartphone too much. You hear people say all the time, “I hate this stupid phone. I wish I could just ditch it.” So why don’t you? “Well, I need the Gmail app for work. And I have my whole life on my calendar. And I don’t want to lug around a dumbphone and a digital camera and a GPS…” 

In 2011, just 35 percent of Americans had smartphones. That number is up to 85 percent today. In a single decade, life without them has become literally unimaginable. Nobody asked for it. It wasn’t invented to solve a particular problem. It didn’t fill an absence in our lives. (Just the opposite.) Yet as soon as the iPhone appeared on the market, we all had to have it. 

We don’t own this technology. The technology owns us.

That helplessness is an illusion, though. It’s sort of like a comfort blanket. It allows us to outsource our moral choices—usually to the government. And if that worked, I would be all for it! Believe me, I’m no libertarian.

The trouble is that it doesn’t work. Our lefty friends are right. We have to do something—not Joe Biden, or Nancy Pelosi, or Mitch McConnell, but you and me.

Because this moral outsourcing is part of the problem. It weakens our resistance. If we could pass a law tomorrow banning Americans from owning smartphones, they’d just find something else to be addicted to. And if men like Mr. Yamagami want to take a life, they’ll find a way.

We don’t need better laws. We need better men. We need to be more discerning about which technologies we adopt—and, once we adopt them, we need to exercise more self-control in using them.

That seems obvious, because it is. And yet we never hear anyone say it. Why? Because it would mean dispelling our comforting illusions. It would force us to own our decisions. But the longer we tolerate this moral atrophy, the harder it will be to grow strong again.

“Man is born free,” said Rousseau, “and everywhere he is in chains.” Really, that’s just wishful thinking. Man wraps himself in chains, the way a child wraps himself in his special blanket. It comforts him. It gives him the pleasant illusion of unfreedom.

The truth is that man is free, whether he likes it or not. Until we can wrap our heads around that beautiful, horrible reality, nothing will get better. Nothing at all.