US President’s war powers explained: The American Constitution gives Congress the authority to declare war, while the President serves as commander-in-chief of the armed forces. Over time, however, presidents have launched military operations using Congressional authorisations and executive powers, creating a long-running debate over who truly controls the decision to go to war.At present, America, with Israel, is actively engaged in military operations against Iran. Bombing is rampant. Drones are flying low and hitting targets with precision. And yet, who actually had the legal authority to send the US in war in the first place? It’s a question that has divided lawmakers, presidents, constitutional scholars and most recently the US Senate. What the American Constitution saysThe Founders of the Constitution were deliberate. Having lived under a monarchy, they did not want any one person wielding the full might of the military unilaterally. Article I, Section 8, Clause 11 of the US Constitution grants the Congress — not the president — the power to declare war. That’s the legislature’s job. But they also gave the President something significant: Article II, Section 2 grants the president unspecified powers as ‘Commander in Chief’.ALSO READ | Why Iran’s cheap drones are costing the US millions to neutralise in Middle East war Workers on Wednesday remove the rubble of a police facility struck during the US-Israeli military campaign in Tehran, Iran (AP Photo).What Article I saysSection 8 of Article I says: “The Congress shall have Power to declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water.”It shall also have the power to “raise and support armies, but no Appropriation of Money to that Use shall be for a longer Term than two Years”.Story continues below this adWhat Article II saysArticle II of the US Constitution says: “The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several states.”So who really controls the military? In theory, both branches share that authority. In practice, it has always been messier.As per the United States Senate, “The Constitution assigned to Congress responsibility for organizing the executive and judicial branches, raising revenue, declaring war, and making all laws necessary for executing these powers.”CLICK HERE FOR THE LATEST UPDATES ON THE MIDDLE EAST WAR.Story continues below this adThe US President’s expanding reachPresidents have long pushed the boundaries of their Commander-in-Chief title. The Korean War, Vietnam, Gulf War, Afghanistan, Iraq — Congress never formally declared war during any of these operations. In fact, the United States has not formally declared war since World War II.To fill that legal gap, Congress developed a workaround: ‘Authorizations for the Use of Military Force’ (AUMFs). Mark F Cancian, a senior adviser at the Center for Strategic and International Studies, was quoted as saying by PolitiFact that this “legislative vehicle has become the modern version of a declaration of war”.Last year, Trump seemed to try and expand his war powers by rebranding the ‘Department of Defense’ to the ‘Department of War’. The objective was to go on an offensive when required rather than deploy military only for defense.In its document “Declarations of War vs. Authorizations for Use of Military Force”, the US Congress says that the Supreme Court of the United States has construed the ‘Declare War’ clause to mean “not only that Congress can issue formal declarations of war, but also that it can authorise the use of armed force for more limited operations short of a full-scale war”. “For example, Congress passed and the President signed into law statutory authorization during the Vietnam War, the Persian Gulf War of 1991, the post-September 11, 2001 invasion of Afghanistan, and the 2003 Iraq War,” the document reads.Story continues below this adThe 1973 check on Presidential powerFrustrated after Presidents dragged the country into Vietnam without meaningful Congressional input, the Congress passed the War Powers Resolution of 1973 over President Nixon’s veto, intending to reassert its authority over wars.The law creates a clear set of rules: the president can only introduce US armed forces into hostilities if Congress has passed a declaration of war, issued a specific authorisation, or if there is a “national emergency created by attack upon the United States, its territories or possessions, or its armed forces”. Friends Committee On National Legislation Without one of those three triggers, any military engagement must end within 60 days, plus a 30-day withdrawal window. The Joint Resolution of November 7, 1973, that introduced clauses to limit the war powers of the US President (Nixon Library).Why President’s war power is under the lens now?On February 28, 2026, the United States and Israel launched military operations against targets in Iran. President Trump did not seek prior Congressional authorisation for what he dubbed as “Operation Epic Fury”. In a notification to Congress on Monday, Trump said: “Our objective is to defend the American people by eliminating imminent threats from the Iranian regime.”The Senate on March 4 rejected a bipartisan war powers resolution that would have directed the removal of US forces from hostilities against Iran. Trump supporters have backed his actions, citing precedents.Story continues below this adHowever, the difference between an “attack” and a “war” often comes down to duration and intensity. And Trump has himself confirmed that the US was at war with Iran.“The lives of courageous American heroes may be lost, and we may have casualties. That often happens in war,” he said in video statement. “The United States Munitions Stockpiles have, at the medium and upper medium grade, never been higher or better – As was stated to me today, we have a virtually unlimited supply of these weapons. Wars can be fought “forever,” and very successfully, using just these supplies,” Trump said a day ago.The Senate can ratify his actions, but whether his “war powers” were exercised legally can best be decided by the US Supreme Court as in previous instances.