US Guardian article today April 7:
" The more immediate legal framework is the Geneva conventions of 1949 onwards, which both countries have ratified. Article 33 of the Fourth Convention explicitly prohibits collective punishment of a civilian population. Article 54 of Additional Protocol I – whose core principles are binding as customary international law even on states, like the US and Iran, that never ratified it – prohibits attacks on infrastructure indispensable to civilian survival...."