The many war crimes the US has committed are the main reason they don't want to participate or recognise the ICC. They don't like it when their people get punished for their war crimes and will threaten their alies with invasion to make sure nobody dares to try.

Murdering people on international waters is not even the latest war crime, IIRC the Hague Invasion Act was created because of the war crimes they were comitting in the Middle East 25 years ago.