The ICC is an intergovernmental organisation and international tribunal seated in The Hague, Netherlands. Established in 2002 under the multilateral Rome Statute, the ICC is the first and only permanent international court with jurisdiction to prosecute individuals for the international crimes of genocide, crimes against humanity, war crimes, and the crime of aggression. As of January 2025, 125 states are party to the statute. As USA, Israel, Russia, North Korea, Iran and other countries haven't ratified the Rome Statute, they can do as they please on these territories without being accused, but not in the countries who are members. So what exactly is your problem? The legal authority is clearly defined for those who joined. https://en.wikipedia.org/wiki/Rome_Statute https://en.wikipedia.org/wiki/International_Criminal_Court