OTTAWA — The Conservative government's inability last summer to clearly articulate and defend Canada's mission in Afghanistan was a source of great frustration among the country's top military commanders, Defence Department sources say.

The vexation was vented at a Sept. 6 meeting involving senior federal officials and Chief of Defence Staff Gen. Rick Hillier.

At the meeting, called to discuss the dispatch of reinforcements including tanks to help in the battle for Panjwai, Hillier reportedly said that critics of the war had enjoyed an "open field" to "degrade public support for the mission," said a source who asked not to be named.

As casualties mounted through the summer, opposition to the war galvanized and found a rallying point in NDP Leader Jack Layton's call for a withdrawal of Canadians from combat operations.

Layton has called for Canadian troops in the south to take up a peacekeeping function similar to the role being played by some European NATO members in northern Afghanistan.

Defence Minister Gordon O'Connor's public efforts over the summer were largely limited to a series of photo-ops and written statements honouring casualties.

His most substantive comments about the conflict in months were made outside Canada, to a foreign news agency, while touring Australia and New Zealand.

In those remarks he suggested military victory wasn't achievable in Afghanistan - something he quickly clarified in hastily arranged telephone interviews with Canadian media.

In the absence of political leadership, some commentators came to term the bloody struggle to wrest control of southern Afghanistan from the Taliban as "Hillier's War" - a galling description for officers who say the quotable and accessible general is just doing his job.

"He has no problem defending the mission or speaking on behalf of the men and women in uniform, but until recently the government had not stepped up to the plate," said one Defence Department official who spoke on condition of anonymity.

"Now that Parliament is back they're being forced to defend the deployment."

A spokesman for O'Connor didn't deny the military's criticism, but rejected the notion that the Conservatives failed to defend the mission at a crucial time.

"Canada's new government remains one hundred per cent behind our troops in Afghanistan," said Etienne Allard.

"Our record is one of providing extra resources for the military and promoting the mission on the international stage."

The Conservatives have visibly defended the war over the last month, an effort largely led by Prime Minister Stephen Harper.

Before leaving for a trip to Afghanistan, Hillier was asked if the government had been slow in defending the mission, and if it had done enough to explain the importance of the military effort to an increasingly skeptical public.

His answer was deftly political. He didn't deny the frustration of fellow officers, but focused on the positive.

"Clearly the prime minister has been very articulate, particularly in recent days in the speeches that he's made," Hillier said following a support-the-troops rally on Parliament Hill.

"He's laid out why we're in Afghanistan and why we're committed to that mission in a way that we as soldiers accept that we have a noble cause. You're clearly going to have to do work constantly to keep Canadians satisfied so that they know and understand what we're doing and support it."

It's not that Canadians "don't get, or fail to comprehend why we're in Afghanistan," Hillier said. "They just need to be walked through why our soldiers are in Afghanistan and what we're trying to achieve there."

Allard denied that public support for the mission has softened since the summer spike in violence.

"Canadians are very supportive of our military, the mission, and the extra resources that Canada's new government is providing to end a decade of military neglect under the previous government," he said in an e-mail reopens to questions.

But a defence analyst said the government was absent during the debate over the summer.

"The government is now learning that it's not enough to have one speech or one media article every month or so on what's happening in Afghanistan,' said Alec Morrison, executive director of the Canadian Institute for Strategic Studies.

"The government has to keep up a constant stream of contact with Canadians because the public is seized with this issue."

The military's private frustration was on public display recently among many who attended the rally to support Canadian troops held Sept. 22.

One of the military wives who organized the mass show of support said Canadians who believe in the soldiers and their mission have not had a way -nor been encouraged - to publicly display those sentiments until it was suggested they wear red on Fridays.