Several defence and government sources say there was a determined diplomatic push in the run-up to last fall's NATO summit to get the Harper government to sign on to the formation, which already counts Denmark, Estonia, Latvia, Lithuania, the Netherlands and Norway among its members.
The British were keen to have the Canadians aboard, given their close co-operation during the Afghan war. They apparently even offered to have the Joint Expeditionary Force do much of its training at Canadian Forces Base Wainwright, Alta.
There were constructive, behind-the-scenes discussions prior to the Sept. 5 gathering of NATO leaders in Wales, but they were abruptly and inexplicably dropped by senior Canadian military leaders, who said the idea required much more study.
The 10,000-member formation, known by its acronym JEF, is expected to be fully operational by 2018 and is intended to respond to international crises on behalf of the United Nations where warranted — or act as major reinforcements for NATO's brigade-sized rapid reaction force, which Canada is also reluctant to join.
The hesitation on both counts stands in contrast to the Harper government's forceful rhetoric in the face of a resurgent Russia, which recently conducted a massive air and sea training exercise in the Baltic region.
On the surface, the British offer appeared to be the perfect vehicle for the military ambition of the Conservatives, who take every opportunity to highlight how they're standing up to Vladimir Putin's regime and doing so alongside allies.
At the conclusion of the summit, Harper said his government was waiting for more information from NATO before deciding if it would participate in the reaction force, but made no mention of the British offer.
That is still the government's position as alliance members wrestle with who will pay for the rapid reaction force, according to senior defence sources.
The country's operations commander, Lt.-Gen. Jonathan Vance, in a recent interview with The Canadian Press wouldn't comment on political aspects, but said from a military perspective joining the British expeditionary force would be a substantial undertaking. It could bind the country to respond in a specific way to a future crisis when the government might favour a different course.
By joining the force without a specific mission, "you're signalling a commitment to future operations, having done the training, that you may — or may not — be able to honour," said Vance.
It's not a matter of Canada being unwilling to respond to international emergencies as much as it is about maintaining the flexibility to chart its own course and decide what military elements it wants to commit to certain conflicts.
"You don't know what else is going to be going on in the world at the same time," he said.
In addition, membership in the British would require training time for an army that is already heavily committed.
The Canadian military has its own exercises at home, including newly added winter warfare training and the annual Arctic drill — known as Operation Nanook. Internationally, it takes part in NATO training and an American-led exercise in the Pacific.
"The demand on each of us as nations to participate in training is very high," Vance said. "So, what we have to do is limit ourselves so we don't spread ourselves out too much. We have to be selective."
NDP defence critic Jack Harris said his party agrees with the notion of keeping Canada out of the task force.
"It's not something we would encourage outside of NATO, outside of a UN (mandate)," he said. "Committing the military to an international operation is something we expect would happen with full debate and full parliamentary consideration."
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