The Climate Policy Implosion Begins

Elections have consequences, and that sometimes includes even the obscure ones. The latest example comes from the United Kingdom, where last week’s election for a single parliamentary seat has set off debates within Britain’s two major parties over climate policies.

The ruling Conservatives barely held the suburban London seat vacated by former Prime Minister Boris Johnson’s resignation. The Labour Party had been expected to grab the district, which Mr. Johnson won by around 7,000 votes in the 2019 election, and on the same day Labour pulled off a far bigger swing in another by-election in the north of England.

Within hours of the result, it was clear Labour’s loss came down to environmental policies. The Tory candidate to replace Mr. Johnson framed the race as a referendum on London Mayor Sadiq Khan’s plan to expand a tax on older vehicles to crack down on carbon-dioxide emissions. The tax disproportionately hits lower-income households and small businesses that can’t afford to buy newer cars, and it is unpopular.

Message received. Labour Party leader Keir Starmer on Friday called on fellow party member Mr. Khan to “reflect” on whether the extension of the vehicle tax should go ahead as scheduled in August. Over the weekend Mr. Starmer warned party leaders that Labour is doing something “very wrong” if it sticks to unpopular policies such as the car tax.

The London car tax is the latest climate policy Mr. Starmer has ditched as he woos voters ahead of a national election expected next year. He previously softened his line on oil and gas drilling in the North Sea, and he has scaled back Labour’s green spending promises.

The Tories are also starting to rethink the party’s climate obsessions over the past 15 years. Under former Prime Minister Theresa May, the Conservatives passed legislation requiring the U.K. to achieve net-zero CO2 emissions by 2050. One of Mr. Johnson’s signature bad ideas was a plan to ban the natural-gas-fired boilers that more than 80% of English households use for central heating.

Some Conservatives worry such policies will become a liability in the next election, especially if Labour is stepping back from the net-zero cliff-edge. Over the weekend, Tories expressed new skepticism about the gas-boiler ban. Others want Prime Minister Rishi Sunak to delay or abandon the plan to phase out new sales of internal-combustion vehicles by 2030. Costly mandates for landlords to improve the energy efficiency of property also could be rolled back.

This outbreak of climate-policy common sense has caused the true believers within each party to fight back. They say public support for these policies is “very deep and wide,” in the words of Tory Zac Goldsmith. This is belied by the way voters behave when they are confronted with the real costs of today’s climate policies. Mr. Starmer’s dilemma will grow acute as his desire to reassure working-class voters conflicts with the green virtue-signaling of the urban left in his party.

The climate movement has been marked by the contradiction of ever more extreme policies that have little effect on temperatures but meet ever more political resistance because of their costs. The political parties in democracies that recognize reality first will benefit.