More about Morality and Global Warming
There is almost certainly a tradeoff between economic growth and action to reduce global warming. There is room for considerable disagreement about the terms of that tradeoff, but it would be foolish to deny that a tradeoff exists. Future generations are the ones who will benefit most from economic growth. People who oppose action on global warming argue that the negative impact of such action on future generations by reducing economic growth will exceed the positive impact by reducing global warming.*
On the margin, of course, they are clearly wrong, provided that all the relevant functions are continuously differentiable. If there is some positive chance of harm from global warming, then there is some cost that is worth paying in order to reduce global warming. The optimal Pigovian tax is nonzero. It is, however, reasonably argued that some of the relevant functions are not well-behaved. If there is a “critical mass” involved in reducing global warming, the cost of attaining that critical mass may not be worth paying. Or if there is a cost to the precedent of, for example, instituting a Pigovian tax, then even a small tax may be detrimental. I don’t find these arguments convincing, mostly because I think that the expected benefits of effective action against global warming (averaging over the entire range of possibilities) are extremely high, but it is a reasonable matter for dispute (at least theoretically).
The big problem with viewing any issue as a moral one is that it more or less ends the discussion. Those who disagree with you will never be convinced, because their morality is different from yours.
*Another way to put this discussion is that economic growth, properly measured, is by definition the only thing that benefits future generations. Proper measurement would require subtracting the harmful impact of global warming. The question, then, is whether action on global warming would ultimately increase or reduce properly measured economic growth.