There is currently petition citizen initiative underway to urge the European Commission to connect all capitals of the EU with high-speed rail.
I’ve already signed it, are you joining ?
https://europa.eu/citizens-initiative/select-language?destination=/initiatives/details/2023/000004
Edit: It’s not a petition, it’s a citizen initiative.
Neither are the southeast Balkan countries (GR, BG, RO), or the Mediterannean island ones (MT, CY).
Running a line through Hungary-Romania-Bulgaria-Greece should relatively be much easier though
In theory yes, but:
EU politics is so much fun! :)