@AndreasSebayang Population density is a very good point. Although, looking at the connections to #Urumqi and #Lhasa, it seems to me (as a non-expert) as if their was also a political project behind it that aims at national unity for the #PRC.
The #EU could have their own political #rail project for a democratic version of unity for the continent, too.
But that would of course require money + the guts to stand up to corporate lobbying from the automobile & airline industry.