Will the US officially declare war on Iran by December 31, 2026?

US military operations against Iran began on February 28, 2026, with joint strikes alongside Israel that targeted military sites, nuclear facilities, and leadership, including the death of Supreme Leader Ali Khamenei. Despite months of sustained conflict, missile exchanges, and involvement in the Strait of Hormuz crisis, Congress has not passed a formal declaration of war, consistent with constitutional requirements and post-WWII precedent for executive-led actions. Negotiations produced a June 2026 memorandum of understanding and subsequent talks mediated in part by Oman, though July saw renewed strikes and Iranian demands for concessions or reparations before full reopening of shipping lanes. As of early August 2026, reports indicate US military leadership seeks de-escalation options amid munitions shortages, with ongoing diplomatic messaging and potential off-ramps under discussion. Any formal declaration would require congressional action and could hinge on whether talks collapse or major new escalations occur before resolution windows close.

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