Chicago likes to think of itself as a “Silicon Prairie” hub of tech startups. And in a recent report on US “startup communities” and their readiness to capitalize on “next-wave startups,” the city ranked 14th. (Boston and the Bay Area were tops.)

So OK, but hardly impressive given both Chicago’s size and proximity to two elite universities, Northwestern University and the University of Chicago. Clearly city officials there, like their counterparts around the country, hope a winning bid for Amazon’s second headquarters might catapult them into the top tier.

Yet given all that, why on earth would Chicago Mayor Rahm Emanuel propose a tax on ride-hailing companies like Lyft and Uber? Seems sort of anti-tech. I mean, I get the basic reason: It’s a way of raising revenue for the city’s public transit system. But more broadly, the tax might be an effort to help bolster public transit in the face of a competitive threat from ride sharing companies. It’s becoming an evermore common story: Public transit problems boost Uber and Lyft, to the detriment of public transit.