The fact that Utah has so many highways is a curious accident---we just happened to be along the way.
After all, SLC is not exactly in the big leagues insofar as metropolitan areas go.
And that doesn't seem likely to change.
But High Speed Rail really isn't about city size... it's about city PAIRS. What do you 'pair' any of Utah's cities with? You need distances of about 250-350 miles for a good high speed rail pair.
Denver is 378,
Boise is 338,
Las Vegas is 416,
St. George simply isn't large enough.
And between Denver and the Wasatch Front lies the Rocky Mountains, no friend to railroads, let alone high speed rail. Even the Western High Speed Rail Initiative doesn't consider Boise to be viable. (Why Reno is considered to be viable I cannot guess. )
There is a certain logic to the proposal--all suggested HSR routes follow existing railroads.
But the game has changed a little bit since the railroads were built-- we have this funky new thing called air travel. I was discussing air service earlier today. If a long distance trip is worth making, the airlines usually have route connecting the two cities.
Perhaps the Federal funding process should start classifying transportation funding by modes, and making states pick--"High Speed Rail or Air Travel?".