But he's also disappointed that Prime Minister Stephen Harper hasn't framed Canada's commitment to a six-month combat mission in Iraq as a crucial test of that international doctrine.
If he had emphasized the doctrine and dispensed with political games, Axworthy believes Harper could have won all-party support for committing Canadian fighter jets to participate in U.S.-led air strikes against Islamic extremists in Iraq.
Axworthy was foreign affairs minister in 1999 when the Liberal government of Jean Chretien was faced with a similar decision over whether to join a NATO air campaign against the former Yugoslavia — a mission which ultimately won support from all five parties in Parliament at the time.
The air strikes accomplished their goal of ending Yugoslavia's brutal war in Kosovo and set a precedent that eventually led the United Nations to adopt the responsibility-to-protect doctrine.
The doctrine, which Axworthy says Canada effectively authored, requires the international community to step in if a country cannot protect its own people from atrocities.
"I think if the (Iraq) mission had been put forward in those terms ... then I think it would have developed a much stronger bipartisan base for consensus in Parliament and in the country," Axworthy said in a telephone interview from Italy, where he doing academic work on the doctrine as resident at the Rockefeller Foundation's Bellagio Centre.
"This is not the time to be playing sort of silly, petty politics on this. I mean this is a serious, significant issue. Thousands of people are being murdered."
But even if the Harper government didn't adequately make the case for the responsibility to protect, Axworthy said he can't understand why Justin Trudeau's Liberals did not.
"That's my disappointment was here's a chance for Canada to really say, 'Look this is one of the most crucial issues of our time. How do we stop this kind of wilful murder and violence and atrocities that we've seen in Rwanda and northern Congo?'
"You've got to realize that diplomatic niceties are not going to work, humanitarian aid is not going to work if people are going to be shot in their beds ... At times, you have to toughen up."
Axworthy's comments came as Trudeau was fending off suggestions that Liberals are divided over the Iraq mission. Several party luminaries from years gone by have supported the mission and one current MP, Irwin Cotler, abstained from a vote on it on Tuesday night.
Both the Liberals and New Democrats, who also voted against the Iraq combat mission, are skeptical that Canada's military involvement can be kept to a mere six months. While he hasn't ruled out seeking parliamentary approval to extend the mission, Harper has vowed not to let it evolve into a years-long, messy "quagmire."
Axworthy criticized all parties for promulgating the notion that the responsibility to protect innocent civilians can be contained to a few months or even a few years.
"If you're going to really provide that kind of international protection, you've got to be prepared to do it properly and do it in a way that doesn't simply allow you to pack your bags and get out as soon as you can," he said.
Axworthy said Canada and its allies can't repeat "the big mistake" they made in Libya in 2011, when an international air campaign succeeded in stopping the killing by Moammar Gadhafi's brutal government but then "everybody packed up and went home and they left a vacuum for the warlords and militias to fill in again."
Noting that Canada stationed peacekeepers in Cypress for 30 years, Axworthy said: "Why do we all of a sudden come to the conclusion that our international responsibilities are sort of short, 30-second clips?"
He believes ground troops may eventually be necessary to root the Islamic extremists but he said they don't necessarily have to come from Canada.