The damage is done. Even if President Barack Obama decides to approve the Keystone XL pipeline at some point in the future, he already sent a message to Canada that our northern neighbor can’t rely on us as its only energy customer — and Canadian prime minister Stephen Harper heeded it.

In an interview with former U.S. Rep. Jane Harman (D-Calif.) in D.C. yesterday, Harper explained that Canada will now seek to expand its export market to Asia and will also cease to supply oil to the United States at a discounted rate.

“Look, the very fact that a ‘no’ could even be said underscores to our country that we must diversify our energy export markets,” Harper told Harman in front of a live audience of businesspeople, scholars, diplomats, and journalists. …

Harper also told Harman that Canada has been selling its oil to the United States at a discounted price.

So not only will America be able to buy less Canadian oil even if Keystone is eventually approved, the U.S. will also have to pay more for it because the market for oilsands crude will be more competitive.

“We have taken a significant price hit by virtue of the fact that we are a captive supplier and that just does not make sense in terms of the broader interests of the Canadian economy,” Harper said. “We’re still going to be a major supplier of the United States. It will be a long time, if ever, before the United States isn’t our number one export market, but for us the United States cannot be our only export market.

“That is not in our interest, either commercially or in terms of pricing.”

“We cannot be, as a country, in a situation where our one and, in many cases, only energy partner could say no to our energy products. We just cannot be in that position.”

Harper’s comments came the same day that Barack Obama’s Super PAC, Priorities USA, released an ad that sought to tie Mitt Romney to Big Oil. The ad was itself a response to an ad underwritten by the American Energy Alliance that attacked Obama on his energy record and warned that this administration would be content to see gas prices rise as high as $9 a gallon.

This fallout from the president’s decision on Keystone XL underscores the truth that Obama does not make policy decisions in a vacuum. He’ll do what he will — and other countries will respond accordingly. Our famously “cerebral” leader might have preferred to have had more time to “sufficiently review” the project, but he didn’t. In the time frame he was given, he made his priorities perfectly clear: He cares more to retain the support of certain constituencies than to approve a project that would have created thousands of jobs and signaled to Canada that we’re committed to ensure a supply of affordable energy for ourselves. The American Energy Alliance had it right: The president’s energy policies have done nothing to secure America’s energy future. We’ll be ever more at the mercy of the oil-producing countries the president likes to blame so much.