We should be building high speed rail every where. Electric planes are not very feasible with current technology, but electric trains are.
Last mile problem. Only like 10 US cities have good public transit within the cities. Driving still wins in many high speed rail cases vs a fast train and expensive cabs or uber to get around.
How is that any different than an Airport?
The infrastructure between airports is more flexible and has lower upfront costs making it more accessible to private enterprises.
High speed trains travel times are underestimated, they need to have the same security screening requirements as commercial airlines.
Why? They're on a track.
Being on a track changes little, a bomb going off in a train at 140 MPH can easily kill as many people as one going off in a plane at 500 MPH.