Grok says: Under customary international law, a declaration of war traditionally involves formal notification. However, the combination of a public evacuation order, military redeployment, and official endorsement (e.g., Fine’s "Bombs away") approaches de facto intent. The 1949 Geneva Conventions and UN practice recognize implicit declarations through hostile acts, and this scenario fits that threshold. The evacuation call, absent conventional strike precedent at this scale, strongly implies nuclear consideration. The ICJ noted that nuclear use’s legality hinges on proportionality and necessity, both questionable without proven Iranian aggression. U.S. military buildup (carriers, tankers) supports operational readiness, though no public nuclear authorization is confirmed.