You may have heard that California Gov. Gavin Newsom’s climate regulators have ordered automakers to give up on the gas-powered cars, pickups, and SUVs consumers love and begin a forced march toward selling 100% electric vehicles in that state by 2035.

Better pay attention: When it comes to Mr. Newsom’s Green Dream for the auto industry, what happens in California won’t stay in the Golden State.

If allowed to remain in force, the governor’s regulatory edicts will override the judgments of policymakers nationwide and dramatically narrow the vehicle options available to American families. That’s because California’s market is so big and important that automakers have little economic choice but to spend tens of billions of dollars converting their entire production systems and fleets to comply with the state’s activist climate rules.

When popular models disappear from dealerships and the price of all vehicles rises significantly, hundreds of thousands of jobs will be lost in the domestic auto industry. Worse, traffic deaths and injuries will jump in every part of the country as millions of Americans are stuck driving older, less safe vehicles. Our already vulnerable power grid will be strained beyond limits by an accelerated switchover to battery-powered cars. And of course, the United States will come to depend on China even more to supply the inputs EVs require.

>>> California Dreamin’ —A No-Choice Nightmare That Benefits China

But by federal law, the California mandates ought to be dead on arrival.

Congress decided back in the 1970s that our country needs uniform national fuel economy and environmental standards for the auto industry, and it directed the Department of Transportation and the Environmental Protection Agency to establish federal requirements that (1) are feasible for conventional gas-powered automobiles to meet, (2) protect the vitality of our domestic auto industry and the millions of jobs it sustains, (3) preserve a wide range of affordable new vehicle models that America’s consumers want to buy, (4) maintain highway safety and (5) promote national security, including by weaning the nation of dependence on unfriendly foreign powers.

To reinforce these policy directives, Congress prohibited states from imposing any different requirements for new vehicles covered by the federal rules, a broad prohibition meant to foreclose disruptive state auto regulations such as California’s mandates, which work against every one of Congress’ objectives.

So how is Mr. Newsom able to push his anti-consumer campaign against the internal combustion engine? The answer is President Biden.

The EPA has authority to grant California (and only California) a waiver from preemption under the Clean Air Act when necessary “to meet compelling and extraordinary conditions” affecting local air quality.

Congress singled out California for special treatment because of its history of smog, particularly in the Los Angeles region. The Biden administration has now employed this waiver authority to greenlight Mr. Newsom’s radical climate mandates for the auto industry, even though those mandates are motivated by a desire to advance global climate goals, not to address air-quality conditions unique to California.

>>> Why Are So Many Residents Fleeing California?

In the American system of federalism, all 50 states are supposed to be equal in sovereignty and dignity. True federalism means that each state has an equal ability to experiment with different rules in its own local markets, and unless Congress prescribes a national solution, each state can choose to adopt rules that are stricter or looser than those that apply in other states.

That’s not what’s happening here.

Contrary to Congress’ judgment that the auto industry requires uniform federal standards, the Biden administration has used the Clean Air Act waiver process to empower one single state in the Union, California, to dictate a revolutionary new industrial policy for the people of every other state. And the policy mandates Mr. Newsom is handing down are far stricter than anything the residents in most states would find acceptable—if they ever got the chance to decide the question for themselves.

What Mr. Biden has unleashed with his California climate waiver is the antithesis of true federalism.