Comment by AncientTree

High-speed rail is often slower and definitely more expensive than regular rail, if Europe is any guide.

Rail is best used for freight.

Autonomous busses and cars (electric) are the best long-term solution for travel.

The best approach is simply to enact a Carbon Tax and let the market figure it out.

We would be better off promoting mass-contraception to the developing world and halting land clearance in terms of massive targeted CO2 reductions.