1. It was their idea.

2. The benefit particularly of phase 2 will accrue disproportionately to its heartland

3. It is precisely the sort of capital investment in infrastructure that Labour has advocated throughout George Osborne’s plan A.

4. Labour’s respected city leaders in Manchester, Birmingham and beyond were privately apoplectic about Ed Balls’ surprise conference intervention. It is now public. Sir Richard Leese told me last night after I asked him if he felt aggrieved my Ed Balls’s doubts: “We as a country have to get serious about infrastructure”. A letter on behalf of the eight core cities by Birmingham’s council leader was even more forthright.

30 train g w Ten reasons why Labour are bluffing on HS2

5. Labour’s core cities are currently hinging much of their economic recovery plans on huge regenerations, popular with foreign investors of the new high speed rail termini.

6. Most of the shadow cabinet and the leader’s office have been privately reassuring said city leaders

7. As the BBC’s James Landale points out, the money “saved” if HS2 is canned will simply be re-spent elsewhere by the coalition or need to be deployed in the capacity improvements. No cuts will be reversed if HS2 is canned.

8. Pro-HS2 campaigners detect a retreat in Shadow Chancellor Ed Balls’s tone, after the prime minister called his bluff, saying he would cancel HS2 without Labour support. Mr Balls’s team vociferously deny this.

9. There IS some scope for value for money saving. Particularly as HS2 has a giant contingency pot now. New Chairman David Higgins will review starting work on phase 2 (Birmingham to Leeds and Manchester) and finishes before phase 1 (London to Birmingham). This could also shorten the time of delivery into the 2020s. Mr Balls could lay claim to saving this money. Transport Secretary Patrick McLoughlin told me last night: “I’d certainly like it to be quicker … a faster build in from phase 1 to phase 2″.

10. The infrastructure giants say that they can and want to deliver HS2 quickly. It is far, far more likely that HS2 will be delivered more quickly than it being cancelled. Many anti-Hs2 campaigners are convinced that the project will never happen, and are rightly calling out some of the racier numbers behind the benefit: cost ratio.

But your correspondent is making a strong call: HS2 is a done deal, it will sail through parliament, and if anything will be fast-tracked.

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