Saying things is not a war crime. So if Iranian soldiers surrendered to US soldiers and they were shot that would be a war crime. I don't think that happened? Hegseth statements could be used to support the claim of war crime under such circumstances if they were to arise. [EDIT: As a commenter suggests it is possible that simply saying this is a war crime, or at least there are some legal opinions suggesting it]
Attacking civilian targets with cluster bombs has happened and Iran is doing that as we speak. That is a war crime.
Attacking infrastructure is not a war crime if that infrastructure serves a military purpose. Attacking purely civilian use infrastructure is a war crime.
Threatening to attack civilian use infrastructure is not a war crime. Threatening to attack infrastructure used for military purposes is also not a war crime.
Mowing down protestors with machines guns is not a war crime but maybe we should consider it a crime against humanity.
EDIT: FWIW I do care about what Hegseth said. It's wrong and he shouldn't have said that. But people say stuff- what matters are the actions.
Attacking civilian targets with cluster bombs has happened and Iran is doing that as we speak. That is a war crime.
Attacking infrastructure is not a war crime if that infrastructure serves a military purpose. Attacking purely civilian use infrastructure is a war crime.
Threatening to attack civilian use infrastructure is not a war crime. Threatening to attack infrastructure used for military purposes is also not a war crime.
Mowing down protestors with machines guns is not a war crime but maybe we should consider it a crime against humanity.
EDIT: FWIW I do care about what Hegseth said. It's wrong and he shouldn't have said that. But people say stuff- what matters are the actions.