ON Monday, the prospect of a high-speed rail link took a step closer to becoming a reality when MPs voted to give the relevant bill a second reading.

Though there is a long row to hoe, it was a significant milestone in the history of a project that continues to cause controversy. One Tory minister, David Lidington, who missed the debate, insists he will resign if the proposed route does not include a tunnel through the Chiltern Hills, which, you may not be surprised to learn, are in the heart of his constituency.

Such a threat is unlikely to garner much sympathy from the likes of Boris Johnson, mayor of London, who, in hymning HS2, accuses the naysayers of nimbyism while ostensibly trying to protect the countryside. "It's tragic we have protest groups talking about 'this ancient woodland'," said Mr Johnson, who was not previously known as an arboriculturist, "when actually there's no tree in this country that's more than 200 years old. It's b******s. They're not campaigning for forests, they're not campaigning for butterflies ... they're really furious that their house prices are getting it."

Which may well be true. Few of us, one imagines, including even Mr Johnson, would be happy to have trains thundering like juggernauts through what was formerly our back garden and destabilizing our property's foundations. But where the greater good is concerned we must all, it would appear, be prepared to forget base selfishness and make sacrifices. HS2's messianic promoters see it as much more than a railway line. Should it ever come to pass, they trumpet, it will be to 21st-century Britain what Brunel's iron bridges and Stephenson's Rocket were to the 19th: symbols of a progressive, entrepreneurial, connected, imaginative, can-do age.

A key difference between then and now, of course, is that railways in the Victorian age were financed by private companies. In contrast, if HS2 is ever built, it will be underwritten by an acquiescent public, many of whom are unlikely immediately to benefit from it. At present, its cost has been estimated at £45 billion but few even among its advocates expect that to be the final bill. For a sum of that ilk, you could replace virtually every hospital in the land.

What we are likely to get, however, is something rather less useful. As Christian Wolmar, an authority on the railway industry, has written: "To counter the objections the case for HS2 needs to be overwhelming. It is not."

Cost is one concern. Another is the rape of the environment. Yet another is the limited extent of the proposed route, which eventually will link London Euston with Birmingham, Manchester and Leeds. For these cities and their immediate hinterlands benefits will surely accrue but, by far, the biggest beneficiary will be London which is already too big for its boots and which sucks everything into its rapacious, ungrateful maw like a white whale.

In respect of national harmony, this is unhealthy, unwise and unsustainable. Though the Westminster Government pays lip service to the rest of the country, it cannot see much further than the end of the Northern Line. If London booms, so the received wisdom goes, so too eventually will the boondocks. And if you bring the two ever closer then both must thrive. But what if you don't live within a short hop of an HS2 hub? Well, as another Tory minister said in another age, you may need to get on your bike and pedal like Bradley Wiggins.

If there must be HS2 it should come at least as far north as Edinburgh and Glasgow. It would be an indication that Scotland matters to the rest of the UK. Moreover, it would be a practical demonstration of the validity of the Better Together slogan. There is scant chance of that, though. Apart from anything else the cost would be prohibitive.

But in the 1960s and 70s it was planned to do just that. The journey from Glasgow to London was set at three hours which would require trains to travel at more than 125 miles an hour for the length of the journey without stopping. At present, the fastest time between the two cities is four hours and eight minutes.

Come HS2 it could be half an hour less; which, by my calculation, works out at around a cool £1.5 billion per minute.