How Italy's high-speed trains helped kill Alitalia
https://edition.cnn.com/travel/article/italy-high-speed-trains-alitalia/index.html
Basically, it's difficult for air carriers to deprive high speed trains of their passengers, when bullet train can connect 2 cities within 3 or 4 hours.
If traveling time is the same between them, many people would refrain from going to airport located outside of downtown and would want to avoid waiting time at airport.
In countries where high speed rail network is expanding, air liners will have to cope with severe competition with it.
