"Isn't about" is incomplete, but a search for "ISN" or "isn't about" reveals several entities and concepts that "ISN" could refer to, including ISNetworld, a contractor management platform; the International Society of Nephrology (ISN), dedicated to kidney health; ISN Corp, which performs site visits for the Supplemental Nutrition Assistance Program (SNAP); and various other organizations and technical terms like the Bureau of International Security and Nonproliferation or an Initial Sequence Number (ISN) in networking.