In yesterday's throne speech the federal government reiterated its plan to end Canada's military mission in Afghanistan next year. No one can fault Canadians for wanting to conclude this long, costly deployment. But by leaving behind a small contingent of troops to help train the Afghan army, Canada could make a modest but vital contribution to the ongoing NATO operation.

Building Afghan security forces is central to NATO's disengagement strategy. The alliance hopes that the current "surge" of U.S. troops will reverse the insurgency's momentum and buy time to increase the size and capability of Afghan forces, thus making it possible to hand off the lead responsibility for security to Afghan army and police units, province by province, district by district.

Whether this plan will succeed or fail remains to be seen, but in a universe of bad options, it offers the best prospects for gradually ending NATO's massive Afghan mission in a responsible manner. (An irresponsible strategy, by contrast, would be to withdraw all NATO forces precipitously. Doing so would be a recipe for renewed civil war whose destructiveness would likely dwarf the guerrilla conflict now underway.)

In January, the Afghan government and its international backers agreed to nearly double the size of Afghanistan's army within two years. But building such a force will require many more military trainers from NATO countries. In fact, the alliance estimates that it needs 1,600 additional trainers by the end of this year.

That's why NATO Secretary General Anders Fogh Rasmussen and U.S. Secretary of Defence Robert Gates have been urging allies to help. "More trainers are needed, and needed immediately," said Gates recently.

Canada, as it turns out, already has a substantial training team in Kandahar. Called an Operational Mentoring and Liaison Team, or OMLT, it consists of about 200 soldiers -- a fraction of the roughly 3,000 Canadian troops currently in Afghanistan.

The OMLT is divided up into smaller groups and deployed to work directly with Kandahar-based battalions of the Afghan national army. Many actually live with the Afghan units they are mentoring, a practice that reflects a lesson learned in recent years: the most effective way to train Afghan forces is to work with them in the field, rather than to rely on classroom instruction.

The benefits of this hands-on approach are reportedly visible in Helmand province, where NATO is conducting a major operation. Although there have been accounts of poor performance by some Afghan units, the Canadian-mentored units sent from Kandahar to participate in the operation have done a "marvelous job," according to the Canadian colonel who commands the OMLT.

In fact, most of the Afghan units under Canadian mentorship have improved their ability to plan, conduct and sustain their own operations. The training of the Afghan army has been one of the brighter points in what has otherwise been a worsening security situation in Kandahar -- and in Afghanistan -- in the last several years.

The good news is that recent developments in Helmand and elsewhere offer some hopeful signs for the mission. NATO finally seems to have settled on a strategy that seeks to earn the trust and support of ordinary Afghans by providing them with more durable security and basic services. With the addition of 30,000 new U.S. soldiers, it may now actually be possible to hold territory, rather than repeatedly clearing the same villages. And even the highest levels of the U.S. command now seem to understand that reconciliation with some elements of the insurgency will eventually be necessary.

But reconciliation efforts are most likely to bear fruit if the Taliban and its allies believe they are no longer winning the war. The history of conflict resolution elsewhere suggests that peace negotiations are most likely to succeed in conditions of stalemate, when neither side thinks it has a realistic chance of defeating its adversary.

That is one of the reasons Barack Obama agreed to send additional troops last December, and why building the Afghan army is so crucial. Stalemating the Taliban would give Kabul crucial bargaining leverage that it currently lacks with the insurgency -- or, more precisely, with those elements of the insurgency that might be willing to negotiate.

This is the context in which NATO and the U.S. have been imploring allies to provide military trainers. Yet, it is also the moment Canada is declaring its intention to withdraw all of its forces -- including the 200-member OMLT -- from what is arguably the most strategically important part of Afghanistan.

Here is what Stephen Harper said in January: "We will continue to maintain humanitarian and development missions, as well as important diplomatic activity in Afghanistan. But we will not be undertaking any activities that require any kind of military presence, other than the odd guard guarding an embassy."

Strictly speaking, Harper was merely reiterating the terms of the March 2008 parliamentary resolution, which called for the "redeployment of Canadian Forces troops out of Kandahar" by the end of 2011.

But that motion also underscored on the importance of training Afghan security forces. It stated that the "ultimate aim of Canadian policy is to leave Afghanistan to Afghans" and that "in order to achieve that aim, it is essential to assist the people of Afghanistan to have properly trained, equipped and paid members of the four pillars of their security apparatus: the army, the police, the judicial system and the corrections system."

Conditions have changed since March 2008. NATO urgently needs trainers now. The Canadian forces that are scheduled to leave Kandahar next year cannot simply be "replaced" by Afghan forces, as the March 2008 motion anticipated. The time has come for our party leaders to consider a new motion -- one that recognizes that Canada can still make important military contributions to the international mission, even after we withdraw the bulk of our forces from Afghanistan.

The OMLT's mission is a risky job: mentors must travel with their Afghan units, even into combat. But it is also an important task -- one that can be performed by a relatively small Canadian contingent.

Canada has no obligation to keep a single soldier in Afghanistan beyond 2011. The real question is whether we have an interest in providing continued assistance, even modest military assistance, to NATO's ongoing efforts in that country. Unfortunately, the government's all-or-nothing attitude towards Canada's military deployment is short-circuiting that.

Roland Paris is an associate professor in the Graduate School of Public and International Affairs and director of the Centre for International Policy Studies at the University of Ottawa.