Two other recent actions by the administration seem more spiteful. On Sept. 24, Andrew Wheeler, administrator of the Environmental Protection Agency, sent a letter to the state accusing it of failing to meet federal air quality standards and threatening to withhold billions in federal highway funds if California did not do more to clean up its air. Two days later, Mr. Wheeler sent another letter charging California officials with failing to address multiple instances of discharges exceeding federal standards under the Clean Water Act, including pollution from trash, drug paraphernalia and human waste left on the pavement by homeless people in big cities like San Francisco and Los Angeles. (Mr. Trump has blasted state officials for being too tolerant of the homeless, but has offered no concrete solutions and actually cut funding for housing in his recent budgets.)

It is true that California has dirty air. According to the American Lung Association, seven of the country’s 10 metropolitan areas with the worst ozone or smog pollution are in California. There are several reasons: California has a warm climate, a lot of people and vehicles, huge agriculture and fossil fuel industries, and mountainous terrain that traps pollutants in the skies above populous areas. California has long been aware of the problem; that is, in fact, precisely the reason it asked the federal government for permission, in the late 1960s, to set its own strict air pollution standards, permission the Trump administration is now seeking to revoke.

But no similar threats were sent to three dozen other states that, according to The Washington Post, contain counties that failed to meet those national benchmarks for air pollution. Nor were any threatening letters sent to the estimated 3,500 community water systems elsewhere in the country that failed to comply with federal water quality standards.

So what, really, is the purpose of Mr. Wheeler’s public scoldings? To portray Californians as uniquely irresponsible? To deflect criticism from Mr. Trump’s own sorry environmental record? It’s hard to tell, but knowing Mr. Trump and his jealousies, he must hate it that when the world seeks evidence that America cares about climate change, it looks to state capitals like Sacramento and Albany and Olympia, and not Mr. Trump’s Washington. Also, Hillary Clinton’s four million vote margin in the state more than accounted for his national popular vote loss.

Meanwhile, as Mr. Trump’s handmaiden, Mr. Wheeler has done the reputation of his agency no favors. There have been times in the E.P.A.’s long and controversial life when it fell down on the job by abdicating its regulatory responsibilities, as it did during Ann Gorsuch’s reign under President Ronald Reagan. There have been times when it has been accused of overreach simply for carrying out its responsibilities under the nation’s basic environmental laws. But never, so far as we can recall, has it been so obviously deployed as an instrument of political retribution.