//I agree with TTT, freight belongs on the rail for long distance haulage, transported overnight. //
that can't happen. most routes are closed at some point overnight for maintenance, so there's no scope for running overnight freight trains. much of the network operates at capacity now, there are no paths available for extra trains of any description, never mind slow moving freight trains. on many parts of the network (and not just commuter routes) dangerous crush loadings are experienced daily - check out train operator twitter feeds, it's not unusual to be stood wedged in a corner for 3 hours or more.
nationalisation would need to take all of that into consideration; all current trains are privately owned (and leased to the franchises) - just to buy them back will cost about £9bn, never mind the cost for stock already ordered, and more stock to tackle overcrowding. all freight services are privately owned and operated - i'm not sure there's a will - even by mr Corbyn - to buy those back. far better i'd have thought to let truckers operate 80T vehicles, and rail freight will vanish forever.
all in all, nationalisation will come at a cost so huge, that in the medium term it's a practical non-starter.