It began as a good-natured joke at a news conference on Capitol Hill, became a running gag throughout the event and, by the end, it managed to morph into a serious point about U.S. energy security.
Pipeline proponents held the event to bolster their case by pointing to the dispute with Russia.
Their reasoning is that energy dependence leads to weakness — which is why Europe can't impose serious sanctions against Russia, one of its major gas suppliers. In a similar vein, they say, the U.S. lives in fear of instability or hostility in oil-producing countries.
The expanding North American oil-and-gas sector now provides, they say, a historic opportunity to secure supplies from a trusted ally.
That's when the two-century-old conflict came up.
Canadian ambassador Gary Doer noted that it's been a while since the neighbours fought each other.
"Ever since the War of 1812 we've been allies," Doer said, drawing laughs by adding: "I won't get into that war."
Republican Sen. John Hoeven cut him off to say: "We won that war."
But Doer wasn't prepared to let that go unchallenged: "No, no," the ambassador replied. "You did not win that war, senator. I'll show you references."
A few minutes later, Alex Pourbaix, vice-president of pipeline-builder TransCanada Corp., joked that his company has been waiting since 1812 to get its line approved.
It was all wrapped up eventually on a serious note by West Virginia Democratic Sen. Joe Manchin, who described the North American energy surge as a golden opportunity. And he mentioned the War of 1812.
"If we have a reliable partner we don't have to worry about: Is (there) gonna be a coup? Will they change the government? Is it going to be hostile against Americans?
"That has never happened — since 1812. And we don't think it'll ever happen again," Manchin said.
He described the oil-and-gas expansion on this continent as a liberation; a removal of "shackles;" a chance to be a more powerful player on the world stage, capable of helping allies facing an energy crunch.
As if to underscore the point, Ukraine announced Wednesday a 50 per cent increase in gas prices. Fear of an energy squeeze has, meanwhile, helped inoculate Russia against European sanctions.
The U.S. energy supply is undergoing a drastic transformation.
The American Energy Information Administration projects a significant drop in imports from virtually every region in the world, except Canada, which would increase its exports to the U.S. by half and account for just over half of American imports by 2040.
But would Keystone make a difference in Ukraine?
Probably not. KXL would carry oil; the fears in Europe involve Russian natural gas.
But one expert says this project and others, can make a difference in the future.
With Vladimir Putin in Russia, conflict in Nigeria, instability in the Middle East and hostility from the government of Venezuela, the U.S. would benefit from a thriving oil-and-gas sector close to home.
"The number of countries that you could call politically stable suppliers, you could literally count on one hand and Canada's one of them," said Fen Hampson, director of global security and politics for the Centre for International Governance Innovation.
"The situation in Ukraine, Russia, underscores the instability and high political risk that is attached to one of the major producers and exporters of oil. If North America is interested in insulating itself from those shocks, then indeed it makes a great deal of sense to promote local sources of supply."
Keystone opponents reject the idea that it would mean more energy security.
All it would do, they say, is make the oilsands more productive and slow down the transition to green energy that would make the U.S. truly self-reliant.
As for the War of 1812, the two sides never resolved their difference over who won.
But it should be noted that they were meeting in the basement of a building — the U.S. Senate side of the Capitol — that was torched by the British on Aug. 24, 1814.
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