The ICC is bad

That is according to John Bolton and his boss. They have threatened sanctions against the International Criminal Court (ICC) because of two issues:

The first was ICC prosecutor Fatou Bensouda's request last year for a full investigation into alleged war crimes in Afghanistan, which would include any committed by US military and intelligence officials.
Then, a 2016 report from the ICC said there was a reasonable basis to believe the US military had committed torture at secret detention sites in Afghanistan operated by the CIA, and that the Afghan government and the Taliban had committed war crimes.

The ICC was established by a UN treaty in 2002, and has been ratified by 123 countries. The court investigates and brings to justice people responsible for genocide, crimes against humanity, and war crimes, intervening when national authorities cannot or will not prosecute.

Interestingly, China and Russia have not joined the court.