Trains "should replace planes" ???
Well, the London to Paris/Brussels Channel Tunnel train service is no shining example. After enormous investment on both sides of the channel (and under it) a good half of the passenger trains built for it are redundant. Some have been hired to operate out of London Kings Cross to Leeds, while several of the original London to Paris ones have now been transferred away to domestic runs in France. The trains built for the overnight runs from Britain to the continent have been sold to Canada, never having operated. The utilisation of the remaining fleet is way down on original plans, and passenger numbers are about half the expectations. The London to Brussels demand in particular is apparently dropping by the year, as are the number of scheduled runs.
Meanwhile Ryanair have sprung up to Brussels and Easyjet to Paris. The traditional carriers, having taken a big initial hit, are now holding their own or better. So if this one prestige project has been a flop financially, what hope for a whole network?