Have you noticed the huge new billboards on U.S. 191, a major gateway to Yellowstone Park? They seem to be sprouting like mushrooms after a spring rain, but the probable cause is different.

I suspect this furor anticipates regulatory control on more billboards. It is certainly not due to increased traffic and, hence, more viewers. I find these signs irritating and a reminder of an event long passed.

While a graduate student, I had a friend, Josh Brockway we’ll call him, who once came close to being arrested—he was a precocious monkey-wrencher.

It was 40 years ago in Wall, SD, and Josh was driving to Seattle. Every few miles, often less, he saw a sign advertising Wall Drug. One proclaimed, “Everything the traveler wants is in Wall Drug.” This was in keeping with the store’s philosophy: “...you can reach out to other people with something that they need!”

Josh stopped at Wall Drug and asked to buy a can of orange spray paint. “Sorry,” he was told, “we don’t have it.”

Josh asked to speak with the owner, Ted Hustead, and was shown upstairs to his office, where he explained what he wanted. Josh told Mr. Hustead that he saw an excess of signs advertising Wall Drug. Hustead seemed pleased and asked why Josh wanted the orange paint.

Josh said he admired the scenery of Central SD and found the Wall Drug signs distractive and offensive. He also noted that many signs, not all advertising Wall Drug, suffered from bullet holes. The orange paint was to spray bulls-eyes on the worst of the Wall Drug signs.

Hustead wasn’t amused. After a heated discussion, he had Josh ushered out. Waiting at the door were two police officers. They warned my friend that he had threatened an illegal activity subject to prosecution and followed Josh as he drove west.

As a graduate student studying political economy, I found Josh’s story of Wall Drug to be a fine example of negative externalities. Externalities are the costs or benefits of an action that are not born by, and hence are neglected by, the decision maker.

Wall Drug reaped the benefits of their signs. They enticed customers while ignoring the costs of a marred landscape. It’s a precursor to the blight afflicting U.S. 191 today.

Billboards, especially those near a commercial establishment, often convey useful information: “Eat here—Good food,” “Worms and Maggots,” “Diesel $2.69,” “We Dress Deer.” Such signs may indeed be helpful to travelers. Further, they are usually modest in size, though rarely elegant in design.

These signs are not my concern, nor are they ostentatious and distractive. Their externalities are small. I, like many of us, am bothered by the huge, obtrusive, lighted, and garish displays of poor taste intruding upon some of America’s most spectacular scenery.

But what about private property rights? Doesn’t the landowner have every right to use his or her land for such purposes? It depends upon the regulations.

Assume you own a home and a new massive billboard pops up. Your once relatively tranquil and bucolic residence is suddenly assaulted by bright light and obstruction. You are more than bothered, annoyed understates the intrusion, by this monstrosity.

Your property value depreciates, sometimes a great deal. Who would buy in the lee of this structure? What is the new price? What is the character of those who elect to live in such visual squalor?

Here is the important question of political economy: Whose property rights are we to recognize? How will regulators, politicians, and planners deal with this conflict?

Many, but not all, of these questions would vanish if the billboard company had to compensate for the costs imposed. In principle, it is fairly easy to deal with adjacent owners; buy them out by compensating for their lost values. This strategy, however, neglects the diminished experience of the mere passer-by in route to Yellowstone or Big Sky. There is no easy answer. Few problems have perfect or costless solutions.

A likely outcome is regulation. It’s in the nature of things that existing billboards will be grandfathered in. So be it. This may be the most prudent policy aspiration, a peaceful alternative to monkey-wrenching.