The success of inter-city bus services (like Megabus) proves that high-speed rail is needed in the U.S. and would be quite successful:
Air travel, despite its enormous carbon footprint (and meager profitability), is unlikely to be displaced anytime soon as the transportation of choice for long-haul travel. For short distances, the car is still king. But of the most traveled American routes, many fall into this middle category: New York to D.C. (or Boston), Los Angeles to Las Vegas, Chicago to Detroit (or St. Louis), Dallas to Houston (or Austin or San Antonio), Miami to Orlando, Nashville to Atlanta (or Memphis). These routes are too far for a leisurely drive and too near for most Americans to justify the expense, or increasing hassle, of a plane…
In Europe, these are the routes owned by rail, and transit policy experts in the U.S. hope that in coming decades high-speed rail will serve that market. But it’s the intercity bus, the tortoise of the transport world, that is taking over much of the medium-haul market.

