OTTAWA - A new research paper by the Canadian Foreign Affairs and Defence Institute sheds new light on what the military knew before embarking on the war in Kandahar.

Through interviews and documentation, the researchers uncovered how U.S. intelligence agencies warned the Canadian military before their deployment that a resurgent Taliban and al-Qaeda were preparing a "surge" in southern Afghanistan co-inciding with the arrival of NATO troops in Kandahar.

The report, penned by David Bercuson, historian Jack Granatstein and Nancy Pearson Mackie, principally argues that Ottawa must look at its 10 year involvement in Afghanistan and that "unless our politicians and bureaucrats also learned the lessons of the Afghan War, the price paid by Canada and Canadians will have been far too high."

The Canadian general who was in charge of NATO's southern Afghan command, Brig.-Gen David Fraser, and the first battle group commander Lt.-Col. Ian Hope were given a briefing in August 2005 and "told by US intelligence officers that the Taliban were on the strategic defensive but would reassert themselves" in the coming months.

"U.S. Special Forces believed even then that the Taliban were actually beginning to form shadow governments in the south, the classic mark of insurgency," said the research report, released on Sunday.

Hope received an even more explicit warning in January 2006 that came directly from the American general in charge of U.S. Central Command CENTCOM, the headquarters that oversaw the wars in both Iraq and Afghanistan.

Gen. John Abizaid told him to expect a surge.

The research paper noted the opinion among the Americans, on whom Canada relied for most its war-time intelligence, was not unanimous and there was institutional dissent.

"The U.S. Army, unfortunately, disagreed with these dark assessments and believed that the situation in the rural areas was stabilizing."

It is the clearest assessment to date about what Canadian officials were told prior to the deployment of combat troops in the winter of 2006.

Both the Liberals, who ordered the Canadian troops into Kandahar, and the present Conservative government have repeatedly said they were taken by surprise by the strength of the Taliban onslaught in the spring of 2006.

Following the end of the combat mission last summer, questions have begun to emerge about how Canada became lodged in the brutal guerilla war for so long.

The country's top military commander defended the intelligence community in an interview with The Canadian Press earlier this year and said no one "fully expected" the kind of war that unfolded.

"We're not the only ones to have gone through this kind of discovery because intelligence is never perfect," said Gen. Walt Natynczyk, the chief of defence staff. "Our guys worked very, very hard with intelligence, but the fact is you cannot assess all of the factors, or understand all of the ingredients that go into a counter-insurgency."

The report examines in detail what it calls Canada's "over-reliance" on NATO and in particular the reluctance of other member nations to join the fight in southern Afghanistan.

U.S., Canadian, British, Dutch and Danish troops did the bulk of the fighting, while other members placed restrictions on their forces about how and where they could be employed. It is a pattern that has repeated itself in the current Libyan air war, which NATO has led.

The study recommends Ottawa cast a skeptical eye on future alliance missions.

"NATO is divided both politically and militarily and any national caveats which limit the alliance's ability to succeed politically and militarily in any conflict must be clearly enunciated by all partners at the outset and taken into consideration in Canadian mission planning," said the report.

"Canadian decision makers should think long and hard before entering into any coalition to which national caveats have been attached."

The report also argues for the government to establish clear "political and military objectives" before troops are deployed into combat.