HSR would have to compete with the current airline system. If it's cheaper, more convenient to ride, and the time required to travel is comparable to airline, it could catch on, but as it stands I'm unsure if there's enough room for it to survive while competing against the airline system.
Commercial airlines travel at around 500-600 miles per hour, so if a HSR system is able to reach 220mph, then the plane will get you there about ~2.5x as fast. Of course. People consider their time to be valuable, so if you need to get somewhere quick, you'd likely just take the airplane, unless you're traveling somewhat nearby (like San Francisco to Los Angeles). It would appeal to most people not having to deal with the TSA, but there's no guarantee TSA wouldn't decide that it's their duty to "protect" (terrorize) the people in the HSR system as well.
Somebody please write me a message to convince me my message is nonsense and that a HSR system is a great idea.