Would I expend money to prevent a possible future catastrophe? Of course the problem is that if I do expend the money, and the dire future never occurs, I can never be sure that the prediction was right in the first place.
Nevertheless the nations of the world are focused on that very question. Slowly but surely they are inching forward, collecting data, creating hypotheses and experimenting. Above all they are bargaining. Unfortunately the Lima communiqué notes that there is a still significant gap between the pledges to mitigate greenhouse gases and what is needed. Indeed it was reported in the Times last Saturday that the Lima conference itself had a “vast carbon footprint” as the electricity for the event had in the end to be supplied from diesel generators - something of a PR disaster!
Nevertheless we have to hope that the “boiling frog” is not a correct analogy for our current state. Prevention is always the least-cost option.