Yeah my understanding is that the Railways are already effectively nationalised. What isnt is the companies running the services.

I'm broadly supportive of nationalisation, as I am with water (as opposed to say telecommunications or bus travel where privatisation works) but I dont think it's a panacea at all and I dont think TfW is better for being government run really. I also think it's important than any new British Rail does not have a monopoly. If someone with private rai stock thinks they can run a Cardiff to Bristol service better then they should be allowed to compete.