re: #58 Racer X

New York to Boston is about 200 miles. Putting in a maglev to compete with airline shuttle flights would not be cost effective or sustainable because the maglev trip would be more expensive then an airline shuttle. This could be accomplished with high speed heavy rail with a speed of 200 mph and remain competitive to attract airline commuters.

Tunneling is a rather expensive and labor intensive proposition. It would have to combine tunneling with above elevated track. Elevated track would be the most cost effective. Tunneling requires crossing underground utilities which would have to be realigned and that includes electric, gas, water, telecom, etc. Tunneling also undercuts existing structural foundations which means you would have to add in the cost of retrofitting those existing building foundations.