After the Iranian oil crisis of 1979 began sending gasoline prices soaring, President Jimmy Carter went before the nation from the Oval Office, wearing a sweater, and advised the citizenry to turn down thermostats to save fuel, and money.

After the earlier OPEC oil embargo that tripled gas prices, President Richard Nixon signed a 55 mph national speed limit in 1974; nine states had already reduced their limits to 50.

Safe to say, President Joe Biden won’t be going on television anytime soon to ask Americans to make personal sacrifices to conserve fuel in response to the Ukraine crisis.

There are some good reasons for this. Any bump from Ukraine is likely to be short term; the earlier price shocks were much larger as a proportion of the American economy.

The twin recessions caused by the 1970s price shocks were a significant part of the discontent that elected Ronald Reagan in 1980, and led to scrapping of the New Deal consensus that produced a long era of bipartisanship that’s now but a nostalgic glow.

The other reason, though, is less encouraging. Asking for sacrifices, always unpopular, is now impossible for any elected leader thinking of running again.

Since Reagan’s election, the Republican Party has been overwhelmingly, almost gleefully against taxes of any kind or shape. So it was no surprise that, with gas prices suddenly above $4 a gallon, Maine’s Republicans called for an immediate suspension of the state gas tax, currently 30 cents a gallon.

Paul LePage, their presumed nominee for governor, earlier advocated a 50% reduction, and his presumed opponent, Democratic incumbent Janet Mills, quickly said she’d consider the idea, while not actually endorsing it.

With so much consensus around a gas tax holiday, you’d think it would be a good idea. It isn’t. It’s a terrible idea.

For one thing, there’s too much uncertainty. Since the waning of the pandemic, gas prices have been increasing steadily, and have risen close to $2 a gallon since the pre-pandemic period. They could go up further, or decline.

Even chopping the entire state tax would make only a small reduction, and that’s dependent on dealers passing along the savings — far from guaranteed.

Despite the aversion to any hint of sacrifice, Mainers are pretty resourceful, and have already factored higher prices into daily routines. To a significant degree, driving is discretionary, and our mass movement online over the past two years means there are new options available.

The real reason why suspending gas taxes would be damaging is that they’re far too low already. The last time the federal government raised gas taxes — wait for it — was 1993, and that was supposed to be a “carbon tax” scaled down from Vice President Al Gore’s original ambitious proposal.

In Maine, Gov. Angus King proposed a nickel increase in the late ‘90s, and was amazed at the controversy it generated; he had to settle for 3 cents. King did get the Legislature to start indexing the tax to inflation to keep its value from eroding, as the federal tax has continued to do.

For about a decade, the gas tax inched up gradually, though it still fell far short of overcoming the deteriorating transportation infrastructure virtually every state is experiencing.

Then LePage, on his earlier tour of duty, took care of that, banning indexing and leaving the tax stuck at its inadequate, and effectively declining, level.

Instead, he developed a sudden taste for annual $100 million bond issues, replacing the previous biennial ones. He had to do something; the Highway Fund was hemorrhaging revenue, and the construction program withering.

It seemed strange the state was borrowing more and more money to fill this leaky bucket, especially since LePage was blocking all the other bond issues — for water and sewer lines, higher education, downtown reconstruction, public lands — that constitute genuine future investments.

Mills has continued LePage’s policies, with one exception. She’s dumped a significant portion of the general surplus into the Highway Fund, making this the one year we’re spared from voting on yet another bond issue.

As policy, this is irresponsible, and it doesn’t get any nearer the major decisions we’ll soon have to make, including what to do as electric cars replace gasoline models, how Maine can diversify its transportation system to stem global warming, and how much we really want to invest in roads as we wean ourselves from fossil fuels.

Ukraine may indeed be the fulcrum by which many decisions — on alliances, on trade, on the shape of the economy — end up turning. But it’s safe to say that scuttling gas taxes will be no part of the solution.

Douglas Rooks, a Maine editor, commentator and reporter since 1984, is the author of three books. His first, “Statesman: George Mitchell and the Art of the Possible,” is now out in paperback. He welcomes comment at drooks@tds.net