When I said this discussion about international law was not worth taking place on HN, I actually meant it, sorry.

In principle, our diplomats have mentioned "respecting the prohibition on the use of force enshrined in international law and the territorial integrity of sovereign states"

using those words as search terms yields:

https://legal.un.org/repertory/art2/english/rep_supp7_vol1_a...

https://legal.un.org/repertory/art2.shtml

In practice, command responsibility is generally upheld against losing commanders: https://en.wikipedia.org/wiki/Superior_orders

but an effective way to avoid being tried, at least in the short term, is to be a winning commander: https://founders.archives.gov/documents/Adams/06-02-02-0072-...

(Alexander the Great, on his deathbed, was asked who would inherit his empire; whether because he was an early "realist" or because he was apathetic or simply narcissistic [or?], he replied: the strongest)