When President Barack Obama decided in early November to delay a decision on TransCanada's Keystone XL pipeline until after the next election, America's environmental movement celebrated one of its biggest victories in recent memory. And no doubt the news came as a blow to Alberta's tar sands industry, and to Canada's oft-stated dream of becoming the next global energy superpower.

But behind activists' jubilation lurked a somber reality, an untold story with much wider implications. The broader fight to reform Alberta's tar sands, the one which actually stood a chance of breaking America's addiction to the continent's most polluting road fuel, has been quietly abandoned over the past several years. For that we can thank the planet's richest oil companies and their Canadian government allies, who've together waged a stealthy war against President Obama's climate change ambitions.

Their battle-plan is revealed in more 300 pages of personal emails obtained through a Freedom of Information request to the Alberta government. The story in the emails, reported for the first time here in Salon and The Tyee, Canada's leading independent online news site, traces a year in the relationship of Michael Whatley, a GOP-connected oil industry lobbyist and his friend, Gary Mar, a smooth-talking and ambitious diplomat at the Canadian embassy in the Washington, DC.

The messages lay bare a sophisticated and stealthy public relations offensive, one designed to manipulate the U.S. political system; to deluge the media with messages favorable to the tar-sands industry; to sway key legislators at state and federal levels; and most importantly, to defeat any attempt to make the gasoline and diesel pumped everyday into U.S. vehicles less damaging to the climate. The goal of it all? “Defeatâ€