The EGE wrote:2046. The aliens take over in 2036, and it still takes ten years to build anything no matter who's in charge.
But don't worry, Mecha-Mussolini will make the trains run on time.
Note to rail10: There are some proposals out there, like the California High-Speed Rail project, that aim to have TGV speeds in the next decade. Take a look through that thread if you'd like answers to your question.