Trains do something to me. I love them and cannot help it. My favourite means of travel, the railways are for me more than a convenient way of getting from A to B, but a kind of recreation too. Since first I was a parliamentary candidate for a Derbyshire seat, thousands of happy hours have been spent on the train between St Pancras and Matlock — reading, studying, snacking, snoozing, sipping wine — and latterly, as today, for instance, tapping away at my laptop computer.

Nor am I unusual. Grumble though we do, millions of my countrymen share with me an affection mixed (even after all these years) with a thrill at the very sound of a railwayman’s whistle.

Please, therefore, accept that I do not want to be proved right in the suspicion I now relate. For decades it has nagged at me not as something I would like to demonstrate, but as a thought I would be delighted to dismiss if only someone can show me how. But on reading yesterday’s news that the Royal Mail is altogether to cease using the railways to move the mail — and on hearing recently that a return Eurostar ticket from London to Paris would set me back more than £500 — that old suspicion resurfaced.

Has the fixed iron way been overtaken as a cost-effective means of transport? Is inter-city, overground train travel obsolete? Will a long-distance railway ever be able to pay its own bills by charging its passengers the full cost of carrying them? And, if not, what is the moral or political case for forcing the general taxpayer to make up the difference? At the sound of this inquiry I can all but hear readers scramble for entrenched positions. In many minds, railways inspire a ferocious, near-ideological commitment. Railways are seen as more than a means of transport, but a doctrine. The argument for or against rail travel becomes barely distinguishable from the argument for or against public transport — which in turn slips seamlessly into the argument for taxpayer subsidy. Any expression of doubt about whether overground railway projects soak up more public money than they merit is taken as a declaration of indifference to mass public transport, opposition to taxpayer subsidy, or both.

So let me be clear. Not only does the case for mass public transport cry out for attention, but (in my view) that case will grow stronger in the century ahead. In a densely populated country, central planning is vital. Governments must help to deliver what someone once described as the things everybody wants but nobody wants to pay for. This cannot be left to market forces. I accept without question that some forms of public transport need state investment and state subsidy. I will willingly make the case for more of it. Mine is not the proposition that everything worthwhile should pay its way.

Nor would I question for a moment the essential service provided by underground and overground railways in crowded environments: there is simply no other method for moving millions of people into and through congested cities. The case, for instance, for Transport for London’s Crossrail project is unanswerable. In the South East, it is hard to imagine any other way of getting commuters from Essex, Kent and the Home Counties into work every morning.

But in the examples I have cited, the railway has no real competition. Its passengers are a captive market. The need to attract their custom hardly arises because they have no choice: there is little danger that many might be driven away by cost because they cannot park at work, and coach services would soon clog up if many rail commuters switched.

So, Mr or Ms London commuter, I offer no threat to your daily train — though on another occasion I might wonder to what extent you should ask the rest of Britain to help in paying for it. That, however, is more of a political than a transport matter, but at whatever cost and whoever pays, your railway is safe. The station where you wait is, typically, passed by packed trains every two to fifteen minutes for large parts of the day. No highway can move people on this scale without using vastly more scarce land. Underground trains use none.

But the train on which I am now sitting is different. The train we can take to Paris is different. So are those the Royal Mail no longer wishes to use. All are in direct competition with perfectly practical alternative ways of travelling — car, lorry, coach and plane, the last three having as much right to be called public transport as trains. Yet alone among these, the inter-city and rural railways depend on subsidy, and a lot of it. On the Continent they attract even more subsidy. Comparatively few citizens, however, depend on the inter-city or rural railways, and of those who do, many are fairly well-to-do.

What are the arguments for subsidising us?

I shall mention three, all heard often. The first is that if only enough investment is ploughed into the infrastructure and rolling-stock of our railways, they will eventually become sufficiently attractive as a means of transport to pay their own way. This is the “seedcorn” argument.

The second is that even if rail is never profitable in the narrow terms of a company balance sheet, its contribution to the environment through a reduction in pollution from private cars and road-freight would, if quantified, more than expunge the red ink. This is the “kinder to the environment” argument.

The third is that even if only a minority travel regularly by train, some communities depend upon the existence of rail links, while some people (such as the elderly or disabled) could not manage without trains. This is the “special needs” argument.

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