OIL WOES: Protesters against the construction of the Keystone XL oil pipeline demonstrate in San Francisco on October 25, 2011. U.S. President Barack Obama has put the project on hold due to environmental concerns (CFP)

In January, U.S. President Barack Obama delayed approval of a pipeline that would have carried Canadian bitumen from the northern Alberta oil sands to American refineries in Texas. For Republicans seeking their party's presidential nomination, that was bad enough, but then the Canadian Government and Enbridge Inc., a major Canadian energy company, announced plans to build another pipeline, this one from the oil sands across the Rockies to the Pacific coast, from where it could be exported to Asia, specifically China.

In a recent interview with the Canadian Broadcasting Corp., Harper said, "It is in our interests for all kinds of reasons that we diversify our exports, particularly our energy exports. I think the industry will tell you we already pay a bit of a...we get a bit of a discount because we're a captive supplier to the United States. So I think it's in our interests that we sell our energy exports to Asia, just as it is in our interests that we diversify our trade generally."

This was too much for Republican Newt Gingrich, who said his first act if he was elected president would be to overturn Obama's decision and approve the Alberta-Texas pipeline, known as the Keystone XL.

"My message to the Canadian people is don't build a pipeline to China, help is on the way," he said after the Florida primary.

For Canadian China expert Wenran Jiang, Harper's China visit carried an explicit warning to the United States.

"It's not a subtle warning. It's an open warning," Jiang said in an Associated Press report. "Harper has said Keystone was a wake-up call."

Revival

For Canadians, the sight of Harper trying to play China off against the United States takes some getting used to.

For the first three years after winning power early in 2006, Harper relegated Canada's previously warm relationship with China to the deep freeze. He positioned Canada closer to its traditional allies—the United States and NATO—and he and some of his senior ministers made a number of provocative statements on Tibet, Taiwan, human rights and other sensitive issues. When asked about the potentially damaging impact of all this on Canada's relationship with Beijing, an unrepentant Harper said, "I think Canadians don't want us to sell out important Canadian values. They don't want us to sell that out to the almighty dollar."

China, predictably, was unhappy. Harper could live with that—for a time he even seemed to welcome criticism from Beijing—but there was another unhappy group he could not afford to ignore: the Canadian business community. Although Sino-Canadian trade continued to increase, its expansion lagged behind the rapid growth of the Chinese economy. Canada's share of Chinese trade has deteriorated to just over 1 percent from a high of nearly 2 percent. By comparison, Australia—a smaller country that actually is farther away from China—accounts for 4.3 percent of Chinese imports.