With the House of Representatives moving to approve climate legislation, it is of more than academic interest to understand why Congress appears set to adopt the "cap-and-trade" approach to GHG controls, rather than a carbon tax or other mechanism. Rarely, if ever, has any government policy been enacted with the potential to affect so many aspects of the economy and environment. Why take this route? The New York Times offered a timely analysis of the road to cap-and-trade GHG controls here. If you're interested in a pro-carbon tax argument, this essay hits the highlights.