The United States consistently engages in significant military actions across the globe, often involving substantial force, targeted strikes, and profound geopolitical consequences. Despite these operations aligning with conventional definitions of warfare—such as attacking another nation, eliminating its leadership, and attempting to dismantle its military—formal declarations of war from the U.S. Congress have become a relic of a bygone era.
This evolving dynamic highlights a peculiar circumvention of the U.S. Constitution by modern American leaders, particularly noticeable in sustained tensions, as recently observed in the relationship with Iran. What appears to be an act of war is frequently reframed with terms like “military action” or “collective self-defense,” complicating the traditional understanding of conflict.
The executive branch, while sometimes advocating for a stronger, more assertive military posture—even suggesting a return to the “Department of War” nomenclature reminiscent of the World War eras, when American forces were perceived as more consistently victorious—has simultaneously shown reluctance to formally seek congressional approval for these operations.
Historical precedent: When presidents sought congressional approval
Historically, the decision to commit the nation to war rested firmly with Congress, as explicitly mandated by the Constitution. Presidents like Woodrow Wilson and Franklin Roosevelt adhered to this principle, presenting detailed cases to the legislative body before engaging in large-scale conflicts.
Roosevelt’s impassioned plea following the attack on Pearl Harbor in December 1941, famously declaring it “a date which will live in infamy,” was a direct request for Congress to acknowledge a state of war with the Empire of Japan. Congress swiftly responded, formally declaring war.
Similarly, in 1917, after years of attempting neutrality, Wilson sought and received a declaration of war against Germany. His decision was propelled by critical events, including the interception of the Zimmermann Telegram, which exposed a German proposal for an alliance with Mexico against the United States, making war unavoidable in his view.
The shift to “military action” over formal declarations
In stark contrast to these historical precedents, contemporary presidents often initiate military engagements without seeking formal congressional declarations. The Trump administration, for instance, informed Congress of military actions against Iran through a concise two-page document, citing a 1973 law. This document characterized the operation as “military action” undertaken in the name of “collective self-defense,” despite the United States initiating the surprise strike. The term “collective self-defense” holds significant weight, as it is outlined in Article 51 of the UN Charter as an exception to the requirement for UN Security Council authorization for military intervention.
Congress’s attempts to reclaim war powers
The legislative branch, instead of consistently asserting its constitutional authority, has often struggled to mandate a formal debate and vote on authorizing such military actions. Attempts in both the Senate and the House of Representatives to require a vote on the use of force, particularly concerning Iran, have frequently been met with resistance or stalled, reflecting a broader reluctance within Congress to directly challenge executive power in this domain.
Following the Vietnam War, an undeclared conflict that deeply divided the nation, Congress made a concerted effort to reassert its role. The 1973 War Powers Resolution was enacted to ensure that the collective judgment of Congress and the President applied to the entry of U.S. Armed Forces into hostilities, establishing a framework for presidential accountability.
The expansive reach of post-9/11 authorizations
The era following the September 11, 2001, terrorist attacks further eroded the practice of direct congressional consultation for military actions. The Authorization for Use of Military Force (AUMF) passed in 2001, intended to combat terrorism, has been interpreted so broadly that it has been used by multiple administrations—both Republican and Democratic—to justify military operations globally, far beyond its initial scope.
In a notable instance, President Barack Obama’s request for a specific AUMF to combat the Islamic State in Syria faced significant congressional pushback and was ultimately not granted for three years. Despite the lack of explicit authorization, the administration continued its bombing campaigns against the group, highlighting the executive’s capacity to act without direct legislative approval.
Republican leaders at the time resisted new AUMF proposals, arguing against limiting the commander-in-chief’s military options. Then-Speaker of the House, John Boehner, stated that there was no reason to grant the president less authority than he already possessed.
Political divides and the modern commander-in-chief
In the current political climate, congressional majorities, particularly within the Republican party, have often shown little inclination to restrain executive authority in military matters. Any votes on the use of military force tend to fall along partisan lines, a stark contrast to the bipartisan consensus that once accompanied formal declarations of war.
Public statements from lawmakers sometimes reflect this complex stance. A senator, for example, might initially refer to a conflict as a “war” and acknowledge the necessity of ground troops, yet later, when pressed on the lack of congressional authorization, reframe it as a “brief and direct conflict” rather than a full-scale war.
Leaders in Congress, such as the Speaker of the House, have similarly described ongoing military engagements as “defensive actions” or “very specific and clear missions,” distancing them from the legal and constitutional implications of a formal war declaration.
The evolving definition of conflict and self-defense
This pattern reveals a continuous redefinition of what constitutes “war” in the context of U.S. foreign policy. While the term “Department of Defense” replaced the “Department of War” in 1947 to reflect a strategic shift, the underlying reality of ongoing military conflicts persists, often without the explicit congressional mandate that the nation’s founders envisioned.
The debate over naming the conflict with Iran
The situation with Iran encapsulates this dilemma perfectly. What, by any practical measure, constitutes a war—with two nations attacking a third, targeting its leadership, and engaging its military—is not formally labeled as such by the U.S. government. This semantic sidestepping allows for military operations to proceed under various authorizations, avoiding the rigorous constitutional process of a declared war.
The executive branch’s broad interpretation of existing legislation, coupled with a Congress often hesitant to assert its full constitutional powers, continues to shape how the United States engages in international conflicts. This dynamic ensures that while the nation remains deeply involved in global military actions, the formal act of declaring war has become a historical footnote, rather than a contemporary requirement, in 2025.
