There will never be any way of proving to everyone's satisfaction whether or not the Iranians violated international law. It will remain merely a matter of opinion.

The Iranians think the USA violated international law when arresting some of their people a while back. It's all a matter of opinion.

There is absolutely no point in killing a few hundred thousand more people over this latest incident, but I'm sure that doesn't worry whoever would like to have a war over there. War is always good business for somebody.