For over 248 years, Congress has possessed and exercised its constitutional power to declare, enter, and end wars. Examples include voting to allow participation of the U.S. in World Wars I and II.

In 1973, Congress strengthened its constitutional power by issuing the War Powers Resolution (WPR). This resolution requires the President to inform Congress within 48 hours after U.S. forces “are introduced into active or imminent hostilities, or into a foreign nation while equipped for combat,” and the notification must describe the “circumstances necessitating the introduction [and] the estimated scope and duration of the hostilities or involvement.”

On February 28, 2026, President Donald Trump announced the start of Operation Epic Fury: a combat operation against Iran that he publicly stated was a “little excursion.” On March 11, 2026, when asked by a reporter whether the Iran operations were a “little excursion” or a “war,” President Trump responded, “Well, it’s both. It’s an excursion that will keep us out of a war.” President Trump did not get prior congressional approval before entering into that conflict and committing American troops and resources. On June 23, 2026, President Trump submitted a WPR notification, asserting constitutional authority for the action based on his role “as Commander in Chief and Chief Executive and pursuant to [his] constitutional authority to conduct United States foreign relations.”

President Trump believed that he had the authority to use military force against Iran because it was in defense of the United States and its Armed Forces (which the WPR does permit the President to act upon), thereby creating a “national emergency,” and because he believes that the Iran “excursion” does not rise to the constitutional definition of war. Furthermore, President Trump asserted to Congress in a letter on May 1, 2026 that hostilities with Iran have “terminated,” despite U.S. troops still remaining there, and that every time there is a ceasefire, it resets the WPR requirement to withdraw troops within 60 days.

On June 23, 2026, Congress passed legislation directing President Trump to halt military action against Iran and to remove all U.S. troops. In response, the President dismissed the measures as “symbolic and non-binding” and stated that he believed the War Powers Resolution is both non-constitutional and unenforceable.

Beyond legal and constitutional issues, there are several political factors that drive the expansion of the Iran conflict. First, Republican lawmakers are scared to oppose President Trump for fear of not getting re-elected. The President has over $400 million in super political action committee money that he controls; he has issued over 300 primary endorsements in 2026 alone, and he has successfully worked to unseat prominent Republican members of Congress who have criticized or disagreed with him, including Sens. Bill Cassidy of Louisiana and John Cornyn of Texas and Rep. Thomas Massie of Kentucky.

Second, both the President and Congressional lawmakers have been motivated to support Israel in any conflict with Iran, who have been in international armed conflict for around 47 years. Israel believes that it cannot rely on peace treaties to stay safe but instead it must keep its enemies weak through consistent military conquest.Rather than wait for a major war to start, Israel has engaged in numerous small-scale military operations over a long period of time.

Additional motivation for the continuation of the war is the opportunity to control Iran and the Strait of Hormuz. The Strait of Hormuz is “one of the world’s most critical oil transit choke points,” and U.S. control over the strait would protect the global energy market. The strait sees the shipping of over 20% of all global oil, and when Iran closes the strait, prices in both oil and gas increase significantly (Butler). Iran also wants to tax ships every time they pass through the Strait of Hormuz a significant amount. The U.S. believes this is an “excessive maritime claim” because the Strait is not Iranian, but instead international water so there should be no tax.