I’ve always sensed a whiff of sadness in Florida, perhaps because so many people go there to die. Although not us, obviously, because we went for Disney World. Still, terminality is in the air. In Mafia films, Florida is always, literally, the last resort: the place the wheezing hood heads after he’s failed in the Bronx and Vegas and is now unwittingly destined for a one-way trip on a fishing boat.

Somehow, I reckon, they’re feeling the same mystical embalming lure as those Jewish New York retirees who come to trundle their last-ever mobility scooters into their last-ever condominiums. One day, this dangling American dogleg will fall into the sea under the weight of their coastal apartment blocks, as the whole damn country opts to end its days in the sun. Go south, and by the time you’re bouncing over the narrow archipelago towards the Keys where Ernest Hemingway perhaps first thought of shooting himself in the face, it is hard to escape the sensation that America itself is running out of road.

I was there last week and so was Donald Trump, although we did not hook up. He was in Mar-a-Lago, his resort on Palm Beach, where he met the Japanese Prime Minister, Shinzo Abe. That evening, as the pair chillaxed on the terrace, paying guests got to watch them react in real time to news of a North Korean missile launch. One, a retired investor who joined the club three months ago, posted pictures on Facebook. It used to cost $100,000 to join Mar-a-Lago, but since January the fee has doubled. Trump is expected there this weekend, for the third weekend on the trot. So I suppose, if you have $200,000 and an inclination to meet the 45th President of the United States, that’s where you go.

Having neither, I was on the sand an hour’s drive south. As I looked to the sea, the vast Trump International Beach Resort was a few hundred metres to my left, while the equally vast Trump Towers II apartment complex was about the same distance to my right. London snowflake that I am, the real, tangible presence of both frankly came as rather a shock. If I said it was like seeing a swastika banner on the Arc de Triomphe, I would of course be exaggerating ridiculously; but I find on reflection that I am totally going to say it anyway. Wealth is a surreptitious business in Britain, particularly when it is dynastic, scuttling around in Mayfair or Chelsea. Whereas the Trumps, at least in Florida, are so rich that they blot out the sun.

The big question is whether they’re about to get richer. It would be conspiratorial, I think, to suggest that Trump sought the presidency for material gain. But now that he has it, he does seem keen it shouldn’t go to waste. Melania, his haunted wife, is in the process of suing the Daily Mail for £120 million, after the paper foolishly reported false rumours that she had worked as an escort. As the lawsuit puts it, the First Lady ‘had the unique, once-in-a-lifetime opportunity… to launch a broad-based commercial brand in multiple product categories’, which could now be jeopardised. Brazen.

It’s not clear, though, precisely who the Trump brand’s demographic are these days. Mar-a-Lago may lure the millionaire crawlers and arse-lickers, but you run out of those before long. All this week, CNN has been reporting that a whole swath of American retail outlets — Nordstrom, Sears, Neiman Marcus, Kmart, QVC — have stopped stocking the fashion products sold by Ivanka Trump, apparently because nobody wants to buy them any more. Trump himself has been tweeting furiously about this — ‘Treated so unfairly’, ‘Terrible!’ etc — but if consumers simply don’t fancy opening their wallets, then there’s a limited amount his tantrums can achieve. Nobody seems sure whether bookings at Trump hotels are down or not (there are fierce claims in both directions) but last summer, data from Foursquare, a location-tracking app, suggested some Americans had such antipathy towards all things Trump that they were literally avoiding walking past his properties.

Which may be why there have been suggestions of expansion into Argentina, the Dominican Republic, Taiwan, India, maybe Uruguay instead — making one think a little of those rock bands that become so embarrassing at home that they have to go on tour in Germany or Japan. Technically of course, his properties are in the control of his two eldest, shiniest sons, both of whom were opening a golf course in Dubai this week. Yet Trump still profits directly from all of it, and the more his critics scream about conflicts of interest, the less he seems to care.

Which is, surely, the bit you worry about. A few short months ago, we lived in a world where it was considered sleazy that figures formerly in government could make a mint on the after-dinner speaking circuit, or in consultancy. Now the President attacks companies for not selling his daughter’s blouses, worries about how his wife is going to leverage her official roles and spends his weekends in what might as well be a medieval court, owned by him, where courtiers pay him for access to the great USP, which is him. Say what you like about a drift towards totalitarianism, but at least it’s still politics. Whereas this? This is the stench of death. This is broken. This is America running out of road.