That's not a question easily answered though. Assuming complete objectivity, it would mean that you might save an order of magnitude more lives in the future discovering a cure for cancer, for example, at the expense of lives today. Then you're stuck with questions on how to quantify the value of life etc., but the base reality of the fact that you DO save more lives, and therefore, keep more families intact/happy doesn't change. Who matters more? People who died in the process? Or the future ones who will die as a result of inaction in the present?

Not right. Of course in practice that situation doesn't come up, because you can't reliably tell whether you'd save many more people by sacrificing people now.