Prime Minister Stephen Harper told Canadian troops at Kandahar Airfield on Thursday that Canada has played a leading role in improving the lives of Afghans since 2002. (Sean Kilpatrick/Canadian Press)Prime Minister Stephen Harper, making a surprise visit to Kandahar Airfield on Thursday, emphasized Canadian contributions to Afghan development over combat efforts in the war-torn country.

Harper said that when the Canadian mission began in 2002, the Taliban had been running Afghanistan as though it were a medieval country.

"Those dark desperate days have ended. You have brought hope to those who have none," Harper said after landing at the airfield in a new C-17 military cargo plane.

In his comments, Harper outlined Canada's development priorities in Afghanistan, which include giving $2 million in new funding to a UNICEF project aimed at improving education for almost 18,000 children in Kandahar. Canada is also focused on improving the health of Afghans, and has worked to combat polio, he said.

He left the country shortly after addressing the troops.

'We do not measure our success by the length of our stay'

Prime Minister Stephen Harper looks out at the Dahla Dam and Irrigation System on the Arghandab River in Afghanistan, Thursday. (Sean Kilpatrick/Canadian Press)

Earlier in the day, Harper visited the Dahla irrigation dam outside the city of Kandahar, on which the government is spending $50 million to repair and upgrade. Afghanistan's second-largest dam had fallen into disrepair after decades of war.

Harper said repairing the dam and improving its irrigation system downstream would boost agriculture and create 10,000 seasonal jobs.

"We did not come here as permanent occupiers, and we do not measure our success by the length of our stay," he said. "Our mission is to leave Afghanistan to its people as a viable country, as a more peaceful country, a country in control of its own destiny."

Canadian troops are scheduled to leave Afghanistan in 2011.

"You have behind you the admiration and gratitude of an entire nation," Harper told the assembled troops.

Harper said the arrival of 17,000 U.S. troops in the summer will allow Canadian troops to focus more on providing security in the city of Kandahar and spend less time in the surrounding countryside. But he cautioned that the influx of new fighting forces wouldn't necessarily guarantee fewer casualties.

"It’s a dangerous environment regardless. We can’t fool ourselves on that," he said.

Harper and Gen. Walter Natynczyk, the chief of defence staff, then served coffee to soldiers at the base.

The trip is the prime minister's third to Afghanistan.

There are about 2,800 Canadian soldiers serving in the southern province of Kandahar. Since 2002, 118 Canadian soldiers have died serving in the Afghanistan mission. One diplomat and two aid workers have also been killed.