We were literally the first industrial nation. We already have infrastructure, which is why development is so expensive.
We are currently in a political situation with high speed rail. The costs are soaring and it’s nothing to do with neoliberalism, it’s because to build additional infrastructure in Britain you have to bulldoze through existing shit that is owned by people already.
Nationalising the railways did raise costs by about 1/5 in real terms, but we also have some the safest rails in Europe. They also became more reliable and investment increased 9 fold.