He was quite within his rights to make the connection, and, drawing extensively from the head of the Philippines delegation at UN climate change talks in Warsaw, Yeb Sano, to criticise those who deny the existence of global warming.
In the same vein, people who are sceptical of that link and, indeed, the whole idea of climate change should be listened to politely when they express that view.
We are all the losers if those with one viewpoint curtail debate by silencing their opponents. Trying to achieve this by shouting them down smacks of bullying and intimidation.
It does not demonstrate the tolerance that is present in every healthy society and provides room for every person to express their ideas.