VMT Tax

Even though it sounds like something from "The Onion," this article from "The Hill" reports an apparently serious Obama plan to tax cars by the mile driven.  Obama's "Transportation Opportunities Act" apparently builds on a Senate Budget Committee proposal by Kent Conrad (D-ND) to gather revenues by taxing cars:

Among other things, CBO suggested that a vehicle miles traveled (VMT) tax could be tracked by installing electronic equipment on each car to determine how many miles were driven; payment could take place electronically at filling stations.

This is a non-starter.  Why is anyone wasting tax money developing a plan that would require installing government tracking equipment in everyone's car?  And "payment could take place electronically at filling stations!"  -- It already does!  It's called the Federal Gasoline Tax!