What do you call a cause celebre that is a GOOD cause not just a widely-known one?

A cause célèbre that is considered a good cause is often referred to as a "noble cause" or "worthy cause." These terms emphasize the positive impact and moral significance of the issue, distinguishing it from those that may be popular for less altruistic reasons. Such causes typically inspire public support and advocacy aimed at promoting social justice, humanitarian efforts, or environmental protection.