Conservative Canadian pundit Mark Steyn and Fox Business host Stuart Varney laughed at the idea of members of ISIS "sawing" the head off Sen. Bernie Sanders on Monday because the Democratic presidential candidate had linked climate change to terrorism.

During the CBS Democratic presidential debate, Sanders explained how climate change could accelerate terrorism in some areas.

"If we are going to see an increase in drought, in flood, and extreme weather disturbances as a result of climate change, what that means is that people all over the world are going to be fighting over limited natural resources," Sanders said. "If there is not enough water, if there is not enough land to grow your crops, then you're going to see migrations of people fighting over land that will sustain them. And that will lead to international conflict."

In fact, the journal Proceedings of the National Academy of Sciences published a paper earlier this year detailing how climate change increased instability in Syria, which gave rise to ISIS. The Defense Department has also called climate change a "threat multiplier."

But for Fox Business host Stuart Varney and conservative columnist Mark Steyn, who was Varney's guest on Monday, linking climate change to terrorism was unthinkable.

"He's brilliant, that guy," Steyn quipped sarcastically. "I mean, [ISIS leader Abu Bakr al-Baghdadi] will be sawing Bernie Sanders' head off, and he'll be saying as his neck is being sliced, 'Oh, if only we had an emissions trading scheme!'"

"This is insane," Steyn added as Varney cackled in the background. "And it shows the level of delusion and denial among the Western political leadership."

(h/t: Media Matters)