The last three words very true! What a lot of money could be redirected if the project was to be abandoned ... but "they" will say they've gone too far along the road to pull back now, of course.
There are at least two practical problems with abandonment, and believve me as a former rail worker I firmly believe that a project to speed up the railway could have been implemented at a materially lower cost than the sums spent on HS2, but that is another argument!
In my opinion "They" ie HMGovernment of whatever colour believe they have gone too far along the road to pull back now.
They probably have for at the very least these reasons:
1) Contractual obligations, in that if the project were to be abandoned now, the recipients of the contracts would sue (and win) for breach of contract. Not only would the contractors be compensated, they would also receive their legal cost which would be high to say the least.
2) This (1 above) could be overcome if the government involved was prepared to pass laws forbidding any case resulting from the abandonment to come to court if, they could get it through parliament and were prepared to show that they were an anti democratic authoritarian government, I don't think fortunately that either party would want this label available to their opponents to use.
So, where next, and in future? Before they ever surfact major projects must be subject to a real and meaningful public scrutiny with measures in place to overcome the all to often seen "nimbyism"
Difficult, but in the long term best.Any government should be prepared to take difficult decisions for the public good, even if that goos is in the very long term, which I do not believe was the case for HS2.