For more than two centuries, the division of war powers between Congress and the president has remained a subject of intense debate. When the framers of the U.S. Constitution gave Congress the authority to declare war and the president the responsibility to command the military, they lived in a time when warfare moved slowly, and communication was limited. Today, with modern military technology and instantaneous communication, those same constitutional lines are often tested — especially when presidents act without consulting Congress. The issue was reignited recently when President Trump ordered airstrikes on Iranian nuclear facilities without first seeking congressional approval, drawing swift criticism from lawmakers who view the move as a violation of their constitutional role.
Senator Mike Kelly, a Democrat from Arizona, acknowledged on NPR’s Morning Edition that there is little Democrats can do to compel the administration to follow proper channels, but he emphasized the importance of respecting constitutional tradition. “The administration should comply with the Constitution,” Kelly said. “Traditionally, presidents have done that. I know recently that sometimes, with certain actions that are viewed as protecting the safety of our country, presidents can act, and then they should be able to notify us.” Senator Tim Kaine, a Democrat from Virginia, took a more forceful stance during his appearance on CBS’s Face the Nation, stating: “The United States should not be in an offensive war against Iran without a vote of Congress. The Constitution is completely clear on it. And I am so disappointed that the president has acted so prematurely.”
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What the Constitution Says – and What Presidents Actually Do
The U.S. Constitution makes clear distinctions: Article I grants Congress the power “to declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water.” Article II names the president as “Commander in Chief of the Army and Navy of the United States.” This structure was designed to ensure that while the president can direct military action, it should only come after Congress has authorized conflict. Rebecca Ingber, a law professor at Cardozo Law School, says the framers intended war-making decisions to come from Congress. “I think it’s pretty clear that the framers thought that any time we were going to be making the decision to go to war with another country, that was going to be a decision for Congress,” she says.
However, history shows that presidents have long operated in gray areas. One early example was the Quasi War between the United States and France in the late 1700s. Despite the hostilities, no formal declaration of war was ever issued. Stephen Griffin, a constitutional law professor at Tulane Law School, notes that such practices became more common after World War II. The development of nuclear weapons and the speed of modern warfare made immediate presidential responses more practical. “The creation of the atom bomb changed the game,” Griffin explains. Unlike the early days of the republic, where it could take months to move troops, modern scenarios may require immediate action.
The founding of the United Nations also influenced American legal thinking. With the U.S. playing a key role in establishing the U.N. in 1945, the international framework shifted the discussion from declarations of war to the “use of force,” especially since the U.N. Charter allows military action only in self-defense or with Security Council approval. As a result, U.S. presidents increasingly sought legislative approval in the form of Authorizations for Use of Military Force (AUMF) rather than formal war declarations. “The constitutional requirement is about legislative approval,” Griffin explains, “not literally picking up a document that says ‘Declaration of War’ and signing it.”
A History of Conflicts Without Declarations
This shift in practice was evident in several major U.S. military engagements. The Korean War never received a formal declaration. In 1964, Congress passed the Gulf of Tonkin Resolution, which allowed President Lyndon Johnson to escalate military actions in Vietnam, although the resolution was later criticized for misrepresenting events. In 1991, President George H.W. Bush received an AUMF for the Persian Gulf War. In 1999, President Bill Clinton initiated a NATO-led bombing campaign in Kosovo without congressional authorization. In each case, the balance of power tilted heavily toward the executive branch.
In response to the Vietnam War and growing concern over unchecked presidential power, Congress passed the War Powers Resolution of 1973. Its goal was, in part, “to fulfill the intent of the framers of the Constitution” and ensure that both Congress and the president would jointly decide when to send U.S. forces into combat. The resolution requires the president to notify Congress within 48 hours of deploying troops and mandates that any military engagement must end within 60 days unless Congress grants approval or extends the mission. The resolution passed despite President Nixon’s veto.
Michael Glennon, a constitutional and international law professor at Tufts University and former legal counsel for the Senate Foreign Relations Committee in the late 1970s, observed that Vietnam was a turning point. “Vietnam became the turning point for Congress because their constituents were being killed,” he said. Although the War Powers Resolution initially seemed like a meaningful check, Glennon notes that its impact has been limited. Successive administrations have often ignored its requirements or found ways to sidestep them. Presidents have frequently informed Congress of military action, but true consultation — as envisioned by the resolution — has been lacking.
Glennon argues that the Constitution “does prohibit the president from using armed force in attacking a country such as Iran unless there is an attack on the United States or the threat of an imminent attack.” He adds, “That didn’t happen, and I conclude, therefore, that this was unconstitutional.” Still, he concedes that “generally speaking,” the requirement to consult Congress under the 1973 resolution has technically been followed, though often in a limited form. “In some circumstances, Congress has been informed [ahead of time] rather than consulted. That’s not what the War Powers Resolution contemplated.”
Does the War Powers Resolution Still Matter Today?
Despite widespread disregard, the War Powers Resolution has not been completely dismissed by modern administrations. Ingber points out that even this White House has made some effort to acknowledge it. “Even this administration … is at least nodding toward those requirements. Even Secretary of Defense [Pete] Hegseth said, [the administration is acting] ‘in accordance with the War Powers Resolution.'”
Griffin believes this continued recognition of the resolution’s language matters. He says it reflects that the resolution is still widely accepted as constitutionally valid under Congress’s “necessary and proper” clause. If the attack on Iran truly remains a one-time event, Griffin says formal congressional approval may not be legally required. However, “if this turns into tit-for-tat with Iran, Trump should get an authorization. That would satisfy the War Powers Resolution — and strengthen his legal position,” he says.
The Ongoing Struggle Over War Powers
The tension between the president and Congress over control of military actions is not new — and it is unlikely to fade anytime soon. Although the Constitution draws a clear line between declaring war and commanding the military, the practical reality has evolved through history, conflict, and political maneuvering. While the War Powers Resolution was intended to restore balance, its enforcement has proven elusive. The current debate over President Trump’s strikes in Iran is only the latest episode in a long history of unresolved constitutional ambiguity.
