What are the prospects of seeing rocket engines become the standard for commercial aircraft?  It might be a dumb question; I really don't know all that much about the topic.  The reason I ask is that rocket powered aircraft are much faster—and who doesn't like speed?

My concerns are:

1. I don't know whether there any designs that would be economical.  I understand rockets burn a tremendous amount of fuel and that is obviously a limiting factor.
2. There could be safety concerns.  Just because we can do something doesn't necessarily make it a good idea.  We have seen the struggles Musk has had with his rockets.

We keep hearing about all these super trains that can get us from Chicago to NY in an hour, even though the whole idea of traveling on a track at those speeds seems quite dangerous.  However, up in the air there is nothing to hit, which is a different story.