Irrelevant figures underlying UK transport policy

From Lord Adonis' article in The Times:

The passenger and operational benefits of electrification are immense. Electric trains are far quieter, more reliable, less polluting and cheaper to buy and maintain than diesel trains...

Rail electrification is central to the low-carbon plan set out by Ed Miliband, the Energy Secretary, last week. An electric train emits around a third less carbon per passenger mile than a diesel train, and less than half as much as a private car and a quarter as much as a short-haul plane...

Yes, at 'point of use' those figures are probably correct. But, assuming that CO2 emissions are a relevant consideration, which they are, of course, as they are a proxy for use of fossil fuels, which are scarce and expensive resources, what I want to know is what is the 'full cost' comparison?

How much CO2 is used in generating the electricity to power the trains, to smelt the steel to make the trains and rails (which have to be replaced every six years or so, I am told) and to light the stations and the car parks? Sure, aeroplanes are machines that burn fuel, but the air through which they fly is just there, unlike rails or roads. And we worked out elsewhere that in terms of CO2-per-passenger-per-mile, flying is much the same as driving a car with two passengers. And so on.

Rail is a small proportion of total transport and, therefore, of transport emissions, but its capacity to reduce overall emissions is significant if we pursue a relentless policy of both electrification and expansion, including high-speed rail... At present rail accounts for only 6.3 per cent of journeys, half the proportion of Switzerland and a fifth of that in Japan. There is no good reason why Britain should not aim for much higher proportions.

False comparison. Where rail travel really comes into its own is passenger transport in densely populated areas. Ninety per cent of the Japanese live in two massive conurbations. Switzerland is in fact six or seven large self-contained conurbations surrounding some more-or-less uninhabited mountain peaks. I wouldn't be surprised if a quarter or a third of all 'journeys' in the Greater London area are by train, for example. I was speaking to a chap just now who told me that he needed to get back from Edinburgh to London recently, the cheapest train ticket was £129 and a flight cost £12.99. Rather unsurprisingly, he took the 'plane.