David answered: Everything's possible and a function of risk and uncertainty. Given that uncertainty is playing a big role, I'd prefer to act and regret it than not act at all -- ie, the precautionary principle.Perhaps it is not worth making falsifiable statements about what will be true in 10-20 years when the action must be taken now. As you mention in your second comment, I have decided I am pro-(smart)-intervention now. Fine.
Well, then really what you're saying is no, you will never regret your current support for climate legislation, regardless of how the future unfolds.
Given that your current position is literally non-falsifiable, I don't think there's much point in us continuing this discussion.
When would you make up your mind to do anything except nothing?
Let me use another analogy: Would you prefer to save for retirement over the next x years or just assume that you will be dead in x years, so it doesn't matter? I prefer to save: Even though I may be dead, I may not be and then I'd like to have some retirement income.
Bottom Line: Falsifiable statements (and argumentation that hinges on their empirical testing) are only useful when the answer arrives in a timely fashion. The scientific consensus is that global warming/climate change is happening and will get worse. Rather than hope that the consensus is wrong, it's a good idea to adopt and adapt policies that will reduce change and mitigate the harm from it.