taking the railways back into public ownership won't deliver a green agenda, unless they're only talking about passenger operations. logistics in the UK is a mess, due mainly to the road network being utterly choked for large parts of the day. for their green agenda, they need railfreight, but the only way to grow the rail freight business is to let the present open-access operators get on with the job, and provide them with the infrastructure they need with which to do it.
the only other alternative is to allow 80T trucks on our roads, and since another of the green manifesto promises is "no more road building", that could only end in disaster.