There would have to be major changes to the terms of devolution for that to happen. I think though the Welsh Government would like to be able to nationalise the railways in Wales.
That's true, but once again nobody is clear about what "nationalisation" means.
TfW has now got Keolis Amey as a subcontractor, and that contract can be continued or terminated as TfW wants.
If they terminate it, they will need to employ the skills directly and I can't believe the cost will be much different, and TfW will take the risk.
Either way they have public control of the passenger railway within the scope of UK law and the devolution settlement.
The other half of the debate is about control of infrastructure, at present firmly with Network Rail (apart from CVL just transferred to WG).
NR is already a public body, so that is just a debate about the extent of devolution (and funding to go with it).
I doubt TfW wants to be bothered with the responsibility for ORR and RSSB on the wider Welsh network.
TfW are clearly dependent on HMG policy on rail industry structure, and we await the result of "Williams".
I doubt they are going to boot out all private sector involvement in railway operation, but the age of commercial franchises is obviously dead.
The union demands for nationalisation are about who employs the staff and on what terms.
They view nationalisation as a sinecure and permanent job protection.
But they have short memories of BR which cut staff and services regularly, imposed DOO on large chunks of the network, and suffered public-sector pay restraint during every recession.
If anything, privatisation has become the gravy train with guaranteed jobs and benefits in most parts of the railway, tied into franchise renewals and NR's CP cycle.
And finally, the obscure debate about a "level playing field" with the EU will determine what degree of freedom the UK will have to subsidise the economy, including rail.
That is partly why TOCs have to operate as commercial bodies and why service contracts have to be competitively tendered every so often.
Even if we escape from EU rules, HMG may not be inclined to subsidise the railway to its current very high level.