TFA addresses this. It doesn't matter if it was a "mistake": the US acted recklessly "[amounting] to more than mere negligence," even when warned by their own commanders. Ignorance doesn't excuse crimes.

> The UN mission concluded that the strike on Shajareh Tayyebeh primary school constituted an indiscriminate attack causing civilian deaths and damage to civilian infrastructure, amounting to a war crime under international law.

> According to the report, the US relied on intelligence suggesting a senior Iranian military commander was present at the site but failed to adequately verify the information before launching the strike.

> Investigators said the failure to update targeting intelligence and confirm the building was a military objective amounted to more than mere negligence.

> “Rather, the US directed the strikes at the building of the school while being aware of a substantial risk of striking a civilian object and acting recklessly as regards the possibility that this would happen.”