Good inter-city rail routes, even with the admittedly somewhat greater distance between a lot of US city pairs, don't really require the fanciest HIGH SPEED RAIL, and high speed rail itself doesn't really require super fancy technology. Really it's electrified straightish continuously welded dedicated track with its own right of way and few stops. Nothing magical, no MAGLEV required. Just have to spend the money and probably build some tunnels (depending on where).
Sure top speed 180mph trains are amazing, but so are *average speed* 90 mph trains. Well, not amazing, really, but 90mph gives you about 3.5 hours from Chicago to St. Louis. Not a revolution, but certainly better than driving if you have good frequency and reliability.
But having said that, while an improved inter-city train network is nice and perfectly feasible, if I ran the zoo I'd spend all the money on intra-city transit. That'd be the true revolution for daily lives.
Not that it has to be a choice.