John Lundin wrote on Politicus USA in November 2015:

“To paraphrase an old joke, ‘How many politicians would it take to save the world?’ Answer: ‘No one knows. It’s never been tried before.’”

It doesn’t appear to be a popular old joke. “How many politicians does it take to save the World? --- ZERO” was cited on Twitter on June 17, 2012. “How many politicians does it take to save the world? #FunnyIronicQuestion” was cited on Twitter on March 29, 2014.


Twitter
NHS saved Julian
‏@Run4demHills
How many politicians does it take to save the World? --- ZERO.
1:50 PM - 17 Jun 2012

Twitter
Animesh Prasad
‏@anm1988
How many politicians does it take to save the world? #FunnyIronicQuestion
12:07 PM - 29 Mar 2014

Twitter
John Lundin
‏@johnlundin
#COP21: Q - “How many politicians would it take to save the world?” A - “We don’t know - it’s never been tried before.” #climate #Paris
2:25 PM - 16 Oct 2015

Politicus USA
Paris Climate Talks Will Go On. What You Should Know.
By: John Lundin
Tuesday, November 17th, 2015, 11:36 am
(...)
To paraphrase an old joke, “How many politicians would it take to save the world?” Answer: “No one knows. It’s never been tried before.”