Huffington Post: Yesterday President Obama and Canadian Prime Minister Harper talked about Canadian tar sands. They spoke of them euphemistically, calling them “oil sands.” Now, politicians choose words wisely – perhaps they employed the term to make tar-sand oil seem less egregious? PC talk fixes nothing. When I learned Carol Browner, the assistant to the president for Energy and Climate Change, was accompanying the president on his trip to Canada, my hunch was that global warming would be on the …