Almost eight years on, a continued lack of focus and resolve in Afghanistan will be NATO''s undoing, Canada''s former top general warns in a new book.

Retired general and former Canadian chief of defense staff Rick Hillier wrote in his autobiography to be published next week: "Afghanistan has revealed that NATO has reached the stage where it is a corpse, decomposing" and in need of "lifesaving" or "the alliance will be done."

He said the North Atlantic Treaty Organization is vulnerable to "any major setback" in Afghanistan and faces extinction unless it can "snatch victory out of feeble efforts" thus far.

In the book, "A Soldier First: Bullets, Bureaucrats and the Politics of War," Hillier says no Western country had predicted an Afghan resurgence following the early success of the US invasion in 2001.

When Hillier took command of the NATO-led International Security Assistance Force (ISAF) years later, "It was crystal clear from the start that there was no strategy for the mission in Afghanistan," he wrote.