Perusing recent news about the British Highspeed 2 project, the cost explosion is colliding with the political consensus on building that project. A cost increase by 10 billion pounds to 42.2 billion (50 including rolling stock) has prompted criticism. Former supporter Peter Mandelson warns HS2 will be an 'expensive mistake'

But his opinion shifted as the "understanding of the costs and benefits" changed. The original cost estimates were "almost entirely speculative", he admitted. "Perhaps the most glaring gap in the analysis presented to us at the time were the alternative ways of spending £30bn."

... The economic benefits of HS2 were "neither quantified nor proven" and failed to take account of how the money might be spent on other projects instead, he added. These included upgrades to the east and west coast mainlines and improvements to rail services in the regions and provincial cities.

The current transport secretary and his predecessor are defending the proposal:

He said analysis of the costs and benefits of the line from London to Birmingham, Manchester and Leeds had been "robust and thorough". "The analysis shows building the new line was cheaper - plus we'd be benefiting from improved connectivity, reliability, speed and avoid - bar Euston - most of the disruption of a conventional line upgrade."

... "We must build on that consensus by providing up to date and detailed evidence of the benefits that HS2 will bring, including the creation of 100,000 jobs and the economic return of £2 for every £1 invested through linking eight out of our 10 biggest cities.

A 1:2 cost-benefit ratio is a tall order. And this is "cheaper" than what exactly under what concrete objective?

A funny aside: £50bn question: do we want faster trains or limitless clean energy? - "For the same money, you can either shave 35 minutes off the journey between London and Birmingham, or develop fusion power". Fusion power as a source of limitless clean power is orders of magnitude less likely than an economically successful HS2 project.

_{Schengen is toast!}