Take the Arabian peninsula where south of Jordan and Iraq a large rail network of heavy-haul freight and high-speed lines is rising out of the desert while metros and light rail lines are being built in the major cities. In less than a decade this region has become a hotbed of railway investment.

Conversely, the world's richest economy is failing to invest sufficiently in its infrastructure. As Mr Brooks Bentz, managing director of Accenture, puts it, the United States is facing what he describes as a "perfect storm" in the next 25-30 years. "This may sound like a long time, but it isn't that long when you are investing in infrastructure," he told delegates at the inaugural International Rail Infrastructure and Technology Summit (Irits) in Berlin last month. "In the United States we need to invest $US 225bn a year to get our infrastructure back to a state of good repair, but we are spending less than 40% of this at the moment." For example, one in nine bridges are structurally deficient and need urgent repair or replacement.

The need to invest is even more pressing because the US population is forecast to increase from around 300 million today to 420 million by 2050. "Most of the population growth will occur along the coastal areas where the biggest infrastructure challenges are," says Bentz.

As far as the rail network is concerned, Bentz says there is a $US 39bn gap between what the railways can afford to invest and what is needed. Bentz also believes that utilities have a very good understanding of the status of their assets, whereas the transport industry is lagging behind.

Mr Libor Lochman, executive director of the Community of European Railways and Infrastructure Companies (CER), pointed to a similar situation in Europe where 40 years ago 2-3% of gross domestic product (GDP) was invested in transport infrastructure compared with only 1% today. Not only does he want to see greater investment in infrastructure but a rebalancing between road and rail.

The challenge is not simply to persuade governments to increase infrastructure spending, but also to be more imaginative in finding other funding models. As infrastructure schemes by their very nature have a long payback period, in most cases governments will still have to find the initial funding for projects, but over time it is possible to earn a return or even sell the asset.

Mr Rory O'Neal, acting director of London's Docklands Light Railway, speaking at Global Transport Forum's conference on communications-based train control (CBTC) last month, said the return on the investment in extensions to the light metro is typically 20 years. "The return on the investment is there to be harvested in due course," he said

Mr Klavs Hestbek Lund, project director with Metroselskabet, which is responsible for developing the Copenhagen light metro, said that full automation and driverless operation of the system have helped the metro to make an operating profit which is sufficient to cover 50% of the cost of the original line and make a contribution to the cost of the new City Ring Line.

In Britain, the government sold a 30-year concession for the country's first high-speed line, HS1, to a Canadian pension fund. "The government got 45% of the build cost back and it can sell it again in 30 years time," Mr Tim Smart, head of engineering and operations with HS2 (Britain's second high-speed project), told Irits delegates.

While Bentz believes the 21st century is likely to be "the golden age of railroading because of rail's ability to handle to large volumes of people and freight in an environmentally-friendly way," there is a development in the car industry which might pose a major threat to rail: autonomous driving of cars and other road vehicles.

Several of the world's leading car manufacturers expect to have vehicles on the market by 2020 which no longer require drivers. This will transform the way cars are used as they should be able to use the road network far more efficiently than now leading to a significant reduction in road congestion and a huge improvement in road safety.

While it will take several years for autonomous cars to become widespread and for legislators to change the law to allow such vehicles to be used without the need for a driving licence, this could have a similar impact on railways as the rapid increase in car ownership did after the Second World War, which would be a perfect storm.

The good news is that railways are for once one step ahead, as we already have fully-automatic driverless railways thanks to the growing application of CBTC to metros. We must now apply the technology to mainline railways to reduce operating costs, increase operating flexibility and reliability, and maximise capacity, and we need to start now to stay ahead of the competition.