Congress and Richard Nixon had no intention to pull a bait-and-switch when the enacted the National Maximum Speed Law (NMSL) on Jan. 2, 1974. The emergency response to an embargo, NMSL (Public Law 93-239), specified that it was “an act to conserve energy on the Nation’s highways.” Conservation, in this context, meant reducing oil consumption to prevent the embargo proclaimed by the Organization of Arab Petroleum Exporting in October 1973 from seriously impacting American production or causing a shortage of oil then used for domestic heating. There was a precedent. A national speed limit had been imposed for the same reasons during World War II.
By the summer of 1974 the threat of oil shortage was over. But unlike the case after the war, many government officials, gently nudged by auto insurance lobbies, argued that the reduced national speed limit would save tens of thousands of lives annually. Many drivers conspicuously displayed their allegiance to the cause with bumper stickers reminding us that “55 Saves Lives.” Bad poetry, you may say in hindsight, a sorry attempt at trochaic monometer. But times were desperate and less enlightened drivers had to be brought onboard. We were all in it together.
Over the next ten years, the NMSL became a major boon to jurisdictions crossed by interstate highways, some earning over 80% of their revenues from speeding fines. Studies reached conflicting findings over whether the NMSL had saved fuel or lives. The former seems undeniable at first glance, but the resulting increased congestion caused frequent brake/stop/accelerate effects in cities, and the acceleration phase is a gas guzzler. Those familiar with fluid mechanics note that the traffic capacity of a highway is proportional to the speed driven on it. Some analyses showed decreased fuel efficiency (net miles per gallon). The most generous analyses reported a less than 1% decrease in consumption.
No one could argue that 55 mph collisions were more dangerous than 70 mph collisions. But some drivers, particularly in the west, felt betrayed after being told that the NMSL was an emergency measure (”during periods of current and imminent fuel shortages”) to save oil and then finding it would persist indefinitely for a new reason, to save lives. Hicks and greasy trucker pawns of corporate fat cats, my science teachers said of those arguing to repeal the NMSL.
The matter was increasingly argued over the next twelve years. The states’ rights issue was raised. Some remembered that speed limits had originally been set by a democratic 85% rule. The 85th percentile speed of drivers on an unposted highway became the limit for that road. Auto fatality rates had dropped since 1974, and everyone had their theories as to why. A case was eventually made for an experimental increase to 65 mph, approved by Congress in December 1987. The insurance lobby predicted carnage. Ralph Nader announced that “history will never forgive Congress for this assault on the sanctity of human life.”
Between 1987 and 1995, 40 states moved to the 65 limit. Auto fatality rates continued to decrease as they had done between 1973 and 1987, during which time some radical theorists had argued that the sudden drop in fatality rate in early 1974 had been a statistical blip regressed to the mean a year later and that better cars and seat belt usage accounted for the decreased mortality. Before 1987, those arguments were commonly understood to be mere rationalizations.
In December 1995, more than twenty years after being enacted, Congress finally undid the NMSL completely. States had the authority to set speed limits. An unexpected result of increasing speed limits to 75 mph in some western states was that, as revealed by unmanned radar, the number of vehicles driving above 80 mph dropped by 85% compared to when the speed limit was 65.
From a systems-theory perspective, it’s clear that the highway transportation network is a complex phenomenon, one resistant to being modeled through facile conjecture about causes and effects, naive assumptions about incentives and human behavior, and ivory-tower analytics.
The Multidisciplinarian 
#1 by False Progress on April 16, 2020 - 12:29 am
“By the summer of 1974 the threat of oil shortage was over….”
Whatever context you put the word “shortage” in, there’s been less total oil in the ground every second since then. Most people don’t think about scarcity until it costs money.
Abiotic oil is a Cornucopian fantasy, yet people keep wasting black gold, including gratuitous idling that burns 300,000+ barrels of oil daily in the U.S. per Argonne Labs, etc.
Driving in states with 80 MPH limits is the height of gluttony since you’re forced to waste fuel or be tailgated. It’s also harder on tires and generally more risky. If ours was a rational species, the speed limit would be capped at 65-70 MPH anywhere.
#2 by Bill Storage on April 16, 2020 - 9:34 pm
My intent in writing this was to contemplate how long it took to recover rights that had been surrendered for a temporary good, not to debate the merits of what some benevolent autocrat might do to prevent his subjects from wasting black gold. I wondered whether there was anything to be learned for the coronavirus crisis from a past situation where citizens willingly surrendered their rights for one reason, though they had no choice, and then found those rights suspended indefinitely for a different reason. The two cases differ in many regards. The two reasons for the NMSL were completely unrelated from each other, preventing oil shortage and saving lives. In the case of Covid19, they are at least related – preventing hospital overload (“flattening the curve”) and minimizing total Covid deaths. Still, some might have strongly objected to lockdown as an appropriate means of achieving the latter goal if, in absence of a need for the first, they had been prevented with the second as basis for lockdown. One might argue that a government deriving its power from the consent of the governed has an obligation to lean toward enacting the will of the governed, at least in a democratic republic. It’s a complex issue, since the rights of the individuals most at risk must be included in any risk/reward calculus. I’m thinking that risk/reward calculus should be in the hands of a broader group than just health care officials ad doctors, since that kind of decision involves values, not just facts and projections about the disease.
I think most readers understood my use of the word “shortage” to be its simplest meaning: shortage is when demand exceeds supply. You can, of course, redefine that term to include consideration of your values, and you can argue that your values should be everyone’s values, but that was not the topic I wanted to cover here.
#3 by False Progress on April 17, 2020 - 12:26 pm
Yes, I was aware you were posting it from a “rights” perspective and had to inject some physical reality, since many presumed “rights” are based on blind faith and denial of nature’s laws. There’s no “right” to burn something that’s getting increasingly scarce, especially when so much depends on it. Gas guzzlers should be seen as pariahs, not patriots.
Almost everyone alive today grew up in a world where energy seemed limitless and they failed to see that we’re just burning ancient capital. Many are suffering from a resource-squandering arrogance that needs to be quelled.
Look up a list of oil-producing nations past peak and logically apply that to the whole planet (cumulative peaking). Shale fracking has become the main source filling in the oil gap after conventional crude (essentially OPEC) plateaued around 2006, largely triggering the 2008 recession later. People forget how costly oil got before the recession “coincidentally” started and got blamed on bad finance.
When the shale bubble bursts and leaves us with permanent costly oil, a global depression could easily happen unless we build out nuclear rapidly now (wind & solar are a scale joke). Tar sands won’t help much, being costly and finite themselves. America alone burns a billion barrels in about 50 days Those who claim that “new technologies” will make oil pragmatically infinite are lunatics in my view. Denial of scarcity is a major brain flaw in this gluttonous species.
#4 by Anonymous on April 16, 2020 - 2:12 pm
The quote about “the threat of oil shortage was over…” need not mean the finite supply in the earth, but instead the regional/political situation that kept some of what was produced from arriving in the US.
Apart from that, and the purpose of this article, though the ultimate amount of oil in the earth is bounded by some number of barrels, the proven reserves increase at times as technology to explore and extract is frequently opened up with new knowledge, regulatory approval, and too many other things to name in this comment box.
#5 by False Progress on April 17, 2020 - 12:11 pm
Anonymous wrote: “….though the ultimate amount of oil in the earth is bounded by some number of barrels, the proven reserves increase at times as technology to explore and extract is frequently opened up with new knowledge, regulatory approval, and too many other things to name in this comment box.”
Translation: Using vague platitudes, let’s ignore the laws of diminishing returns, even though the shale/fracking frenzy is a perfect example of that; likely to peak much sooner than Cornucopians wish it would. https://www.google.com/search?&q=shale+oil+fracking+peak+denial
This reminds me of Julian Simon’s (dangerous for public policy) notion that oil is pragmatically infinite simply because we can’t measure all of it. And he asserted that all resources have endless “substitutes” (pure madness). I doubt someone would use that “logic” with a local water-well their life depended on, but the bigness of the planet leads many fools to see it as infinitely large. http://www.juliansimon.com/writings/Ultimate_Resource/TCHAR11.txt
#6 by Anonymous on April 17, 2020 - 5:11 am
Bill, thank you for getting us back on track and probing deeper.
#7 by Roger R on April 17, 2020 - 2:12 pm
“It’s a complex issue…” Do you think Fauci is independently competent to make the decisions he’s making about lockdown removal timing?
https://www.dailymail.co.uk/sciencetech/article-8227025/Relaxing-coronavirus-lockdown-measures-soon-catastrophic-consequences.html
#8 by Bill Storage on April 17, 2020 - 10:00 pm
I haven’t studied followed Fauci close enough to comment, but I’d like to see a lot more deliberation and collective decision making for key issues. Increasing reliance on experts might be driven in part by what we learn in university knowledge silos – specialists are qualified to make decisions even when they are about what we “should” do. Seems to me the CDC panders to the WHO, who panders to the UN, who is the marxist Club of Rome with lipstick.
#9 by Matthew Squair on July 1, 2020 - 2:41 am
Hi Bill, that steady decrease in fatality rate on the roads is called Smeeds law, which links deaths, to vehicle-miles and population. The more ‘people miles’ on the road the lower the rate of accidents. A lot of debate about why, John Adams believes it’s a risk homeostasis process, more cars, nor accidents reported people get more aware of risk. The take home is that safety interventions that everyone believes should work actually …. don’t. Seat belts being a canonical example.