But Jonathan Mueller, a political science professor at Ohio State University, doesn't believe a distinction should be made between weapons."I’ve never been very comfortable with the idea that killing people with one way is better than killing with another way," he told CBC News in an interview.
In a piece he wrote for Foreign Affairs titled "Erase the Red Line," Mueller said in the First World War, chemical weapons were actually found to be humane compared to conventional weapons. Although they did cause a large number of casualties and took men out of action, only a small percentage of them actually died, he said.
He said questions have also been raised about the number of Iranians killed by gas during the Iran-Iraq war. Of the 27,000 gassed, Iran has said only 262 were killed.
Western agreed that chemical weapons have proven not to be very effective on the military battlefield, but "what that means then is when they're used, they're often used solely as a weapon of terror.
"Militaries can often employ counter-measures when they're used, civilians can't So they're often going to disproportionately kill civilians," he said.
But Mueller said that even Baghdad’s chemical attack on the Iraqi Kurdish town of Halabja in 1988, where 5,000 people were killed, may be an overestimate, coming from Iranian officials eager to boost the numbers of dead. Other reports have placed the death toll from 400 to under 20, Mueller said.
"What you’re doing is arguing aesthetics, the aesthetics of death," Mueller said. "People feel more revulsion for this kind of killing and that's just the way it is.
"Having somebody with their arm blown off with shrapnel and gradually declining and his eyes glazing over hours and then succumbing to shock is also horrible. The key thing is to get rid of murder rather than a particular weapon."