Sen. Bernie Sanders received widespread applause during Thursday night's Democratic Party presidential debate when he challenged what he considered a flimsy question on the issue of the climate crisis and then offered a far-reaching critique about a global system in which trillions are spent on war and destruction but similar investments are not made to address the emergency of global heating.

"The issue, as you should know, what the scientists are telling us, is that they have underestimated the threat and severity of climate change. We're talking about the Paris Agreement—that's fine—it ain't enough." —Sen. Bernie SandersAfter Tim Alberta, Politico's chief political correspondent and one of the debate moderators, asked candidates if they would support federal funding to relocate communities threatened by rising sea levels and flooding rivers, Sanders took issue with the premise of the question.

"With all due respect, Tim, your question misses the mark," Sanders said.

"It is not an issue of relocating people from towns," Sanders continued. "The issue now is whether we save the planet for our children and grandchildren. The issue, as you should know, what the scientists are telling us, is that they have underestimated the threat and severity of climate change. We're talking about the Paris Agreement—that's fine—it ain't enough."

Sanders continued by saying the nation must "declare a national emergency" and touted legislation he has proposed to do exactly that.

"The United States has got to lead the world, and maybe—just maybe—instead of spending $1.8 trillion a year, globally, on weapons of destruction," he continued, "maybe an American president (ie. Bernie Sanders) can lead the world. Instead of spending money to kill eachother, maybe we pool our resources and fight our common enemy which is climate change."

Watch:

Rejoining the Paris Agreement ain't enough. The issue now is whether we save the planet for our children and grandchildren. We need a Green New Deal. #DemDebate pic.twitter.com/UFtTkH2z2w — Bernie Sanders (@BernieSanders) December 20, 2019

Climate campaigners applauded the answer as the top moment of the debate up to that point.

.@BernieSanders redirects the #DemDebate questions on the climate crisis with some perspective: "The issue now is whether we save the planet for our children and grandchildren." Biggest applause so far of the night. — Sunrise Movement (@sunrisemvmt) December 20, 2019 https://t.co/O52w63ss57 pic.twitter.com/Hc31esFaqd — Sunrise Movement (@sunrisemvmt) December 20, 2019

"Thank you BernieSanders," tweeted Friends of the Earth, "for continuing to call for the bold solutions that match the scale of crisis we are facing."