Does anyone remember the issue that Stephen Harper called "perhaps the biggest threat to confront the future of humanity today"? No, it wasn't terrorism. Or nuclear proliferation. Or the rickety global financial system. Or a coalition of the socialists and the separatists. Come on! He said this only three years ago. Surely we are not such a nation of amnesiacs and flavour-of-the-month media that we have forgotten the prime minister of Canada warning citizens about the most terrible danger in the world? Or maybe we are. Anyway, this matters because things happened last week that say a great deal about Stephen Harper. So let's nail this down. What did Stephen Harper say is the biggest and scariest threat in a world of big and scary threats? Climate change. Yes, really. Stephen Harper, the Honourable Member from Oil Sands and Mordor, said climate change is "perhaps the biggest threat to confront the future of humanity today." He said that in 2007. Which is only three years ago. Technically, at least. Politically, it feels like the Edwardian era. "It's crystal clear," wrote the editor of the Globe and Mail, in January, 2007, that "the environment will be the single most important issue of 2007." He was right. Canadians told pollsters climate change was their top worry, by a big margin. Two-thirds of Canadians considered it a "very serious" problem. In no other developed nation was concern higher. This surge in green sentiment was a problem for Stephen Harper. His 2006 campaign platform hadn't even mentioned climate change. His environment minister, Rona Ambrose, was a hapless rookie. Lots of Canadians doubted whether Stephen Harper even accepted that climate change was real, let alone a major threat. The Conservatives slumped in the polls. So Stephen Harper got religion. Ambrose was replaced by John Baird, the prime minister's personal pit bull, which alarmed environmentalists until Baird explained how deeply and passionately he felt about the fight against climate change. When a windstorm blew down trees in Stanley Park, Baird flew into Vancouver to be photographed looking gravely at the damage. Of course it was absurd to link one particular windstorm to climate change, and even odder that Baird hopped a jet spewing vast volumes of carbon dioxide in order to make a show of his concern, but that wasn't the point. The point was the Conservatives cared about climate change. Really, deeply, truly. Why, climate change is "perhaps the biggest threat to confront humanity today," Harper declared. You want concern? How's that for concern? But talk is cheap. On substance, the government hardly budged. There were some modest concessions but nothing that remotely matched the rhetoric. Most importantly, the government didn't put a price on carbon emissions. That's the key. Nothing will change without it. And the government wouldn't go there. Environmentalists smelled a rat. At international conferences, the Conservatives seemed to work with the Bush administration to forestall serious change. When the government released its much-touted action plan, Al Gore thunderously denounced it as "a complete and total fraud." Which was fine with the Conservative base. Not so fine with others. Climate change is "the Achilles heel" of the government, wrote the Toronto Star's astute political observer Chantal Hebert. An election is likely and it will be dominated by "the unprecedented high profile of the global warming issue." And that is indeed what happened. Almost. Stephane Dion made the "green shift" the centrepiece of the Liberal campaign in September, 2008. But Stephen Harper countered with a proposal for a cap-and-trade system -- to be constructed in concert with the American government. Then the financial system collapsed. In the economic disaster that followed, the media forgot about climate change. Public concern ebbed. In the U.S. presidential election, both Barack Obama and John McCain committed to a cap-and-trade system but climate change was hardly mentioned. When Obama took office, the recession and health care consumed all his attention and political capital. Even with Democrats in control of Congress, modest cap-and-trade legislation failed to pass this summer. Meantime, the Republican party swung hard right on the issue. In the midterm elections last week, control of the House of Representatives passed to the sort of Republicans who hear "Commie plot" instead of "climate change." And then, with exquisite timing, environment minister Jim Prentice -- whose biggest accomplishment was renting some pandas from China -- quit the government. His replacement is John Baird. Except this time, the job will only be part-time for Baird, which demonstrates exactly how important it is to Stephen Harper. So what does all this tell us about the prime minister? Two things. One, his reputation as a master of political strategy is sometimes deserved. Climate change really did jeopardize his government in 2007. He dodged the danger. And he did it without actually doing anything he really didn't want to do, like putting a price on carbon emissions. The other thing we learned is that Stephen Harper will say anything to win. But I suppose we knew that already.