I used to think that high speed rail was the solution to the problem of domestic aviation’s greenhouse gas emissions, but I’ve changed my mind. HS2 has all the makings of a complete disaster. It has become abundantly clear that its price cannot be contained, so the standard cost/benefit ratio has been revised downwards ever since the first estimate of its costs came in. Its costs won’t just be financial, of course. There is a carbon cost in its making—all that carbon intensive concrete for example—coming at a time when we are supposed to be heading towards net zero carbon (if we can believe Johnson is the least bit interested in that subject). Then there is the opportunity cost, that is, what could have been done with all that money if it was spent on something else? Rail journey times and punctuality could be greatly improved at a fraction of the cost of HS2. Our existing rail network could be improved, e.g. with more passing loops to better accommodate faster and slower trains, with more electrification and simply better maintenance. In my mind there is something rather stupid about the idea of travelling from York to London, via Birmingham to cut a few minutes off my journey time. Perhaps it’s time we learnt how to go a bit slower and make better use of our time. And start taxing aviation fuel to reflect its external costs, namely its impact on the climate. But HS2, very much like Trident is a super expensive vanity project and who are the vainest people in the land?