Probably no single event highlights the strength of Campbell's argument (on peak oil) better than the rapid development of the Alberta tar sands. Bitumen, the world's ugliest and most expensive hydrocarbon, can never be a reasonable substitute for light oil due to its extreme capital, energy, and carbon intensity. Bitumen looks, smells, and behaves like asphalt; running an economy on it is akin to digging up our existing road infrastructure, melting it down, and enriching the goop with hydrogen until it becomes a sulfur-rich but marketable oil.