“Dear prime minister, if you meet another leader who says climate change is not real what will you do to tell them it’s real?”
So asks a young chap called Joe in a question and answer session with Canada’s prime minister that was posted online this week.
Given Justin Trudeau’s team likely had the Q&A well in advance to ensure there were no banana skins (why do you think Fidel Castro is so great?) his answer is as revealing as it is punchy.
“It’s about doing the right thing and doing the smart thing,” says the 44-year-old, who has painted Canada as a climate champion since taking office in November 2015.
Then he lays out his playbook for talking up climate action to this “leader”, who just might be based a few hundred miles south in Washington DC come January.
“First I’m going to talk about the science. We’re going to encourage anyone who has questions about climate change to listen to all the major science organisations and top scientists who know climate change is real and that human action is mostly responsible for it, and I’ll appeal to the sense that we have to work hard today to build a better future for tomorrow.”
But Trudeau knows the old science line doesn’t always work. He knows that some world leaders – say for example the future US president Donald Trump – think climate change is a hoax made up by the Chinese.
So he’s got a few other plays up his sleeve. “If that’s not enough I will also talk about the opportunity that comes with climate change that fact that we should be investing now in cleaner technology,” he says.
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He’s going to say cutting greenhouse gas emissions will create good jobs, economic growth and “opportunities” for the world to become less polluted.
“Those are the conversations that I’ll have, respectfully but firmly that we need to act to build a better future with better jobs and a cleaner environment,” he adds.
So there you have it. Justin Trudeau’s climate spiel for Donald Trump, who promised on the campaign trail to quit the Paris climate agreement once he takes office.
By tradition the first foreign trip by a US president is to Canada, so we won’t have to wait long to see if this works.