AMERICA no longer works. The country’s public infrastructure is crumbling. As I write, I’m in New York, having visited Washington DC and San Francisco. Travel, these days, in the States is an arduous and enervating business, given the fragility and unreliability of public transport. Reason: for decades America – once rich and powerful – has neglected to invest in the basic infrastructural sinews that make a country actually function. Conclusion: slowly, perhaps irreversibly, the great capitalist colossus that was the United States of America is in decline.

I took the Amtrak train line from New York to Washington, the main East Coast connection. On the way down, we were delayed for an hour by signal failure. The track bed on the last part of the journey is so uneven that the ride was like being shaken inside a big tin can. Which is odd, given how slowly the trains crawl in comparison to the UK or Europe.

On the return trip to the Big Apple, my train juddered to a halt a scant few minutes outside of Union Station in DC itself. A mechanical failure in the widget connecting the engine to the overhead electrical wires had failed. We sat there for three-and-a-half hours while a diesel rescue engine came down the line to tow us to Baltimore to catch an onward service to New York. With no electricity – and hence no air conditioning or wifi – everyone sweltered. The saving grace was that without wifi, we passengers had to talk to each other.

The problems on America’s rail nationalised system are not accidental. They arise from decades of underinvestment. The system is literally falling apart. Delays are endemic but there is worse: America’s train system is showing the same lack of safety that used to plague the British rail network. In the past 15 months, Amtrak has had five serious crashes. In March, 32 people were injured when a train was derailed in south-west Kansas. Last year, a derailment in Philadelphia left eight people dead and more than 200 injured. Amtrak is, of course, state owned. But no US administration could get away with putting public cash into a public service, so people will go on dying.

Not that flying is any easier. On Monday of last week, there was a malfunction (caused by an electrical fire) in the computer system of Delta Air Lines. Result: massive cancellations and delays to the airline’s flights. This occurred just when American families were headed on their (short) annual vacation. Dear reader, I was travelling on Delta Air Lines on Friday, coming back from San Francisco to New York. Blissfully, I thought the flight disruptions would be over by then. More fool me.

I got to San Francisco airport to discover my flight was delayed by an hour – a warning email arrived only afterwards! The plane then toddled off to the take-off point where the captain informed us there would be a further delay. So we sat trapped in the Boeing 767 for more than another hour, till we got clearance to head off. OK, a minor discomfort. But such disruptions are now the norm in an America that no longer functions.

In fact every major US domestic airline is suffering from repeated failure by ageing computer systems as a result of lack of investment. Why the lack of investment? First, the US airline industry is a cut-throat business so companies cut corners where they can. Second, this is compounded when airlines merge and try to patch together different data and legacy computer equipment – a problem we’ve seen with British banks. Last month, Southwest Airlines cancelled 2,300 flights because of a computer crash and the failure of a backup system. Another 8,000 flights were delayed. Chicago-based United Airlines suffered major computer problems last summer, resulting in more than 1,150 delays. Ditto American Airlines.

Actually, my delayed Delta flight was a bit of a blessing in disguise. To get to San Francisco airport I took the famous BART light rail from downtown San Francisco. Built 40 years ago, the municipally owned Bay Area Rapid Transport system was once seen as a model for providing quality infrastructure in America. Not any longer. On the morning of my departure yet another fire caused the BART system to shut down, followed by long delays on the airport run.

Once again, this was no freak accident. The BART network is old and creaky now, with frequent such failures and delays for travellers. Worse, cost-cutting has made riding the BART dangerous. In January, a passenger was shot dead on a BART train. The crime remains unsolved. It transpires that the vast majority of CCTV cameras on BART trains are either decoys or don’t work.

But America is in love with its gas-guzzling cars, you will say. So investing in public transport will always come last in the Land of the Free. Well, what about the state of America’s highways? Have you driven the road between JFK airport and downtown Manhattan? It is like driving in some Third World country after the monsoon. The holes, traffic jams and delays are like nothing you will find in Europe. In fact, America’s entire road and bridge system is crumbling. Fact: nearly 70,000 bridges in America – one out of every nine in the entire country – is now considered to be structurally deficient. Translation: ready to fall down.

The cause of all this is well known: public spending on infrastructure in America has fallen to its lowest level since 1947. The US used to have the finest infrastructure in the world. It is now ranked 16th according to the World Economic Forum – behind Iceland, Spain and Portugal. Both Hillary Clinton and the odious Donald Trump have highlighted the issue in their campaigns. Hillary proposes spending $275 billion on new infrastructure over five years, plus another $225bn in loans and loan-guarantee programmes. Trump (inevitably) says this is not enough and promises more. But long-suffering Americans should not get their hopes up. I doubt if very much is going to change.

Last week, while Delta Air Lines grounded its planes, the US stock market hit an historic high. The dramatic contrast between this stock-market bubble and the dire state of America’s real economic infrastructure could not be greater.

True, the US is still the global leader in high technology – the one bit of the economy that genuinely works. But giant hi-tech firms such as Apple, Microsoft and Google are holding circa $1.4 trillion in cash in offshore accounts to avoid paying their US taxes. In other words, in capitalist America, the capitalists are content to sit on their profits rather than invest in the physical infrastructure necessary to keep their home country efficient and competitive.

There is a major lesson here for Scotland. Achieving economic efficiency is a long-term game. It requires serious investment over decades. There are no “get rich quick” schemes for building a healthy, sustainable economy.

Our local advantage is that being small and clever, Scotland can take smart investment decisions quickly and deliver on time.

The third Forth crossing has been a triumph for the Scottish Government in this respect. While America is crumbling, Scotland is building.