If you’ve sat in a traffic jam on a highway, you’ve thought to yourself “If they only built an extra lane, I could pass all this congestion. Why don’t they build an extra lane to this highway? Or build an alternative route?”

This type of questioning led to building many new roads and widening many existing ones for decades. Eventually people realized the flaws in that thinking. University of Toronto and University of Pennsylvania researchers Matthew Turner and Gilles Duranton, based on decades of U.S. highway data, developed what they call a “Fundamental Law of Road Congestion.”

Their research led them to conclude that building roads leads people to use them until they reach the original congestion levels and “that an increased provision of roads or public transit is unlikely to relieve congestion and that the current provision of roads exceeds the optimum given the absence of congestion pricing.”

In other words, roads create traffic, not relieve it. The causes and effects are complex, but you can conclusively say that you cannot decrease traffic congestion in the long run simply by creating more roads. People respond to the amount of uncongested roadway and fill it up.

Decades of planners who increased the supply of roads to decrease congestion decreased it in the short-term in exchange for yet more long-term congestion. They meant well, but their misunderstanding led to the opposite of their goals.

We call The Green Revolution the results of people who looked at starvation around the world and increase the supply of food to decrease starvation. How much does food supply have in common with roads? People say the increased amount of food saved people from starvation. That sounds like building roads decreased congestion, which it does in the short-term, but it recurs in the long-term, leading to more people caught in more traffic jams. Could increasing food supply decrease hunger and starvation in the short-term but lead to more hungry and starving people in the long run?

I don’t have conclusive answers to these questions. I only notice that despite the huge differences between food supplies and roads, there are many similarities. While many people say the Green Revolution saved billions of lives, people also decide how many children they have in part based on economic principles—what resources they have to raise the children and how the children can help them. Could one also say that the Green Revolution led to people having more children that might lead to the same rate of hunger and starvation, just with larger numbers of people?

This issue is complex with many ways of looking at it. I’ve been meaning to write about it for a while, not because I have answers, but to raise a topic I consider important.

If building roads to relieve traffic congestion is nothing like increasing food production to decrease hunger, then there’s no harm in asking. If the two areas are similar, what will we do when the population enabled by the Green Revolution reaches new limits? We’ve continued to build roads to no lasting benefit and much lasting harm. Will we do the same with food?

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