Amusingly, the British government has been trying very hard to pass legislation to protect their own commanders from war-crimes prosecutions.

https://redress.org/news/overseas-operations-bill-passes-but...

Activists managed to limit the most harmful elements of the most recent attempt at this legislation but with the current sudden lurch to the right that's going on, and a completely ineffective opposition, I don't suppose there's anything to stop them having another go at it later.