Liberal Senator Colin Kenny says politicians are too afraid of offending soldiers and their families by questioning Canada's role in Afghanistan, but it's important to have an honest debate about the mission.

"The issue is we've got to do something to get Canadians away from the hush," Kenny said Sunday on CTV's Question Period.

"There's a hush in the country and it's out of respect for the families, it's out of respect for the soldiers. Nobody wants to say anything that could possibly upset the families or the soldiers, and so we don't have a debate."

In a recent op-ed column in the Ottawa Citizen, Kenny called Afghanistan Canada's Vietnam, a war that lasted for more than a decade and left nearly 60,000 U.S. dead.

Kenny, who is also Chairman of the Senate National Defence Security Committee, says his criticism may seem "offensive," but Canadians deserve to know what the government hopes to achieve in Afghanistan before the mission ends in 2011.

Violence in Afghanistan's volatile south has increased in recent weeks, particularly since a U.S. troop surge and a highly contentious presidential election.

Kenny said the increase in violence makes it clear that Canada's strategy to clear, hold and develop former Taliban strongholds is not working.

"Triple D was the answer to things for a while: defence, diplomacy, development. We hear from the government about different innovations, and after a while you're saying, 'I'm sorry, you don't have any credibility,'" Kenny said. "We don't have clear goals in Afghanistan. One of the overwhelming things that comes in my mail is people saying, 'Why doesn't the government tell us what they want to achieve there?'"

Retired Maj. Gen. Lewis Mackenzie responded to Kenny's remarks by saying the increase in violence is in fact a sign that Canadian troops are doing valuable work in Afghanistan.

According to Mackenzie, the influx of American soldiers has allowed the Canadians to concentrate on a smaller area in their fight against the Taliban.

"Violence is increasing dramatically in the south for one reason and one reason only," Mackenzie told Question Period. "That's because we're out there kicking a hornet's nest with additional resources. That's going to happen."

He said Canada's strategy has been hampered by the fact that NATO failed "to provide the resources necessary to take this thing to a proper conclusion early on."

But Mackenzie said with the American surge and President Barack Obama's renewed focus on combating the Taliban in Afghanistan, the new commander of the International Security Assistance Force, Gen. Stanley McChrystal, will adopt Canada's clear, hold and develop strategy.

But Kenny pointed to widespread allegations of voter fraud in last month's presidential election, a thriving drug trade in Helmand and Kandahar provinces and the recent passage of a law that allows for marital rape as signs that the mission in Afghanistan needs to be reevaluated.

"I've come to the conclusion that there's nothing we can do for the 131 (soldiers) that have died except mourn them, respect them, support their families," he said. "And there is something we can do for the next 130 and that is have a really good look at whether what we're doing over there is worthwhile, and maybe get out."