Far be it for me to defend L'il 'B but...
...what war crime? Can I get a specific statute here?
Methinks this idjit is upset about about the US crossing into Cambodia unannounced to kill commies that crossed into Cambodia unannounced and this is the best he can do to muster "intellectual continuity".
There are no statutes on war crimes, they are breaches of customary international law, generally as it may be memorialized by treaties like Geneva/Hague or similar. The Nuremburg and (More geographically widespread) Japanese war crimes trials after WWII are the big point of reference and were based on three categories of crime - crimes against peace (Conducting wars of aggression), crimes against humanity (genocide, ethnic cleansing, etc.) and breaches of the law of war (Geneva/Hague stuff - reprisals against civil populations, execution/mistreatment of prisoners, purposely targeting civilians, etc.).