One of my liveliest conversations during 2016 was over a barbecue dinner in Napa, California. Our host had averred that were Donald Trump to win, it would be because people in the middle of the country were too dumb to know better. It wasn’t the burgers that gave me indigestion.

He was, of course, indulging in an old cliché about American political life: that there are voters on the left and right coasts of the country who see one kind of future and everyone else in the middle who see another. You know, inhabitants of the “flyover states”. We see them from 37,000 feet but would absolutely prefer not to set foot in them unless it’s to visit, say, Aspen.

Maddening were the grotesque generalisations involved. Sorry to disabuse you, chum, but not everyone in New York or California is a progressive liberal! I also wanted to say that it was precisely this kind of condescension that was going to sink Hillary Clinton. And there was this radical thought: those people are American voters too and this is supposed to be one country.

We have a few things to report this week to suggest that on that last point I was being naive.

We will start with automobiles. Driving is driving; there is nothing different about being behind the wheel in California or Connecticut compared with Ohio or Oklahoma. The automobile experience is the same wherever you live, whichever political party you support. America, you might say, was stitched together by the railroads but has become united by cars and the highways they roll down.

Even that may soon cease to be a true statement. Scott Pruitt, in charge of environmental protection (or not) for Trump, is plotting to roll back the CO2 emission rules for cars put in place by former president Barack Obama. Suddenly, the spectre rises of America becoming two distinct markets for cars and trucks, one more or less green the other definitely dirty.

It is a future that even the car manufacturers are in two minds about. On the one hand, they will welcome the main thrust of what Pruitt is expected to announce this week: that the provisions put in place by Obama requiring that by 2025 all cars sold in the US must meet a standard of 54.5 miles per gallon, compared to 38.3mpg today, is just not achievable. On the other hand, they are afraid that Pruitt’s plan could mean the US market being cleaved in two for ever.

The reason for this division are the coasts. They won’t have it. California certainly won’t. The state has a special waiver granted to it by the 1970 Clean Air Act to set its own tough car emission ceilings. The Obama administration essentially toughened the federal standards to match those of California. But if Trump and Pruitt try to roll them back, California’s Democrat leaders will keep theirs in place. Xavier Becerra, the state attorney general, has already said so.

“We’re prepared to do everything we need to defend the process and the standards,” he told The New York Times. “We’re defending them because they’re good for the entire nation. No one should think it’s easy to undo something that’s been not just good for the country, but good for the planet.” California is a huge market all on its own. But 12 other states, mostly in the east and west, not in the middle, have historically followed California’s suit on emissions. Together they account for about a third of all the cars sold in the US.

Conservative forces are already urging Pruitt to try to force California to fall in line. He is primed. The state “shouldn’t and can’t dictate to the rest of the country what these levels are going to be”, he told Bloomberg News. But California won’t give in easily. The upshot might be this: models on sale in showrooms in New York and in Missouri might soon be radically different in design, engineering and even weight.

But finally, more proof that the US is already two countries rather than one, its middle divorced from the outsides, came last week courtesy of Roseanne Barr and the revival by ABC of her late-Eighties sitcom co-starring John Goodman. The first episode of its return drew 18 million viewers, more than any comedy for the past four years. Barr is a Trump fan who plays one. And guess where all the viewers were – in the flyover states. It was huge in Kansas City, Oklahoma City and Tulsa. In New York and Los Angeles it didn’t make the top 20.

This was all by design. The day after Trump’s victory, ABC’s top brass gathered in Los Angeles and debated whether their programming executives had been too busy worrying about viewers on the coasts, liberals and progressives, and not enough about the heartland. “We looked at each other and said, ‘There’s a lot about this country we need to learn a lot more about, here on the coasts’,” Ben Sherwood, the president of Disney-ABC Television Group, revealed to The New York Times.

They were being smart, belatedly seeing what my Napa host failed to – and what Trump clearly saw when he was campaigning. There is another America, the bit in the middle, and it feels neglected.

Naturally, the President has been quick to salute Barr. “Look at Roseanne! Look at her ratings!” he told a union rally in Ohio. “They were unbelievable! Over 18 million people! And it was about us!”