"But to do nothing, when there might be something that could be done, is wrong.My friend's point is that like Al Gore, he thinks it would be immoral to do nothing.
Okay, I'll tell you what. I don't usually ride my bicycle to work this late in the year because of the shortness of the days, but I'll ride my bicycle to work once next week to avoid burning some gasoline in order to reduce global warming. Then I've done "something" about it which means that we collectively have done something about it.
No? I didn't think so.
So what someone really means when they say something like that is that it would be wrong not to do enough to address the issue. But what's enough? There are those who think that nothing short of causing the extinction of all humans via mass genocide and mass suicide is enough. Sure, they're crazy, but the point is that there is a continuous spectrum of opinion on what's enough that ranges from doing nothing to total human extermination.
This spectrum of opinion is based on subjective personal preferences based on the information available to each individual. Combining the personal preferences of a group is the job of politics and democracy and has nothing to do with morality.
Now some will say, "Let the scientists decide." And there's nothing wrong with taking input from scientists. But scientists aren't experts in economics, can't make subjective risk assessments for all six billion of us, and even the debate between scientist who more or less agree about the science will be fierce and political.
In a political debate, a common trick to convince people to join your side is to claim that the issue is a moral one and that you are on the right side of the issue. That is exactly what Mr. Gore is doing when he claims Global Warming to be a moral issue. Indeed, he takes this trick to new heights by claiming it to be the greatest moral issue of our time. Who'd want to be on the wrong side of that? Fortunately, most people with even a modicum of sophistication see right through that ploy.
However, I'm quite concerned with even considering something to be the "greatest" moral issue. That rather makes it sound like a trump card. That is, if two bits of morality conflict, this one wins. Unfortunately, that implies that if mass extermination of humans is required to solve the problem, then so be it.
For that even to be a possibility is immoral in my book.