Is Chicago high-speed rail worth its soaring cost?

Crain's Chicago Business reports:

For years, the state and officials from passenger rail civic groups have argued that a Chicago-based network of trains traveling up to 110 mph could be developed for a few billion dollars, with the key Chicago-St. Louis line within reach for about $500 million. That's not small change, but that's about how much it costs to build, say, four or five miles of an urban expressway.

But now the price has absolutely exploded.

According to a preliminary application submitted by the state to the feds earlier this summer, the cost of a "full build-out" of the Chicago-St. Louis line currently is pegged at $2.42 billion. And that doesn't include a needed $108 million for station improvements, another nearly $200 million for sidings and an undetermined amount for equipment.