The End of Limits on a President’s Wars
On April 22, 1793, President George Washington issued a Proclamation of Neutrality in the war that had just been declared between France and Britain. The United States, Washington decreed, “should with sincerity and good faith adopt and pursue a conduct friendly and impartial toward the belligerent Powers.” Washington’s action raised a question: Where did the President get off declaring the country’s neutrality? After all, the Constitution, which had been written merely six years earlier, entrusted to Congress the power to declare war. Didn’t Washington’s actions infringe on that authority? The dispute generated an exchange over the proper scope of Presidential power, conducted in the pages of a Philadelphia newspaper, between Alexander Hamilton and James Madison. Hamilton, writing as Pacificus, reaffirmed his typically muscular reading of executive authority. A “correct and well informed mind will discern at once,” he asserted, that such discretion “of course must belong to the Executive.” After all, he continued, “The general doctrine then of our constitution is, that the Executive Power of the Nation is vested in the President; subject only to the exceptions and qu[a]lifications which are expressed in the instrument.”
Madison pushed back, under the pen name Helvidius, after the Roman statesman who argued that the emperor should act only with the consent of the Senate. His concern extended beyond the precise question of the neutrality proclamation; Madison offered a more general admonition against bestowing war powers on a single, potentially flawed individual. “In no part of the constitution is more wisdom to be found than in the clause which confides the question of war or peace to the legislature, and not to the executive department,” Madison, the primary author of the document, observed. Were that decision placed in the hands of the executive, he warned, “the trust and the temptation would be too great for any one man”—not, perhaps, “the prodigy of many centuries” but a more imperfect leader, “such as may be expected in the ordinary successions of magistracy.” The reason, Madison said, was clear: “War is in fact the true nurse of executive aggrandizement. . . . In war the public treasures are to be unlocked, and it is the executive hand which is to dispense them. In war the honors and emoluments of office are to be multiplied; and it is the executive patronage under which they are to be enjoyed. It is in war, finally, that laurels are to be gathered, and it is the executive brow they are to encircle. The strongest passions, and most dangerous weaknesses of the human breast; ambition, avarice, vanity, the honorable or venial love of fame, are all in conspiracy against the desire and duty of peace.”
To read those words today, in light of President Donald Trump’s war against Iran, is to shudder. First, of course, at Madison’s prescience: like the other Founders, he grasped the frailty of human nature and the consequent imperative of checks and balances. Second, however, at the chasm between the Framers’ conceptions of Presidential war power and the unbounded nature of that authority today. Even Hamilton took it as a given that the decision about whether to go to war was wisely lodged in Congress, as the Constitution had provided. “If the Legislature have a right to make war on the one hand—it is on the other the duty of the Executive to preserve Peace till war is declared,” he wrote. Hamilton and Madison would have been aligned in horrified opposition had Washington, without congressional action, dispatched gunboats to sink British ships.
But here we are, in a world of congressional atrophy and seemingly unlimited Presidential war-making power. This lopsided situation is not solely of Trump’s making. Congress has not formally declared war since the Second World War, as the executive branch, under Presidents of both parties, has asserted ever-increasing authority to engage in the unilateral use of military force. Since that time, congressional acquiescence has generally taken the form of an authorization for the use of military force—when it has happened at all. To a certain extent, this is a logical and necessary outgrowth of technological innovations, and of the need for speed and flexibility in an age of nuclear weapons and global terrorism. The congressional power to declare war, like the rest of the Constitution, is not, to paraphrase Justice Robert Jackson, a suicide pact. Indeed, the Framers recognized these imperatives, along with the tension inherent between congressional authority and the President’s role as Commander-in-Chief. At the Constitutional Convention, they rewrote the draft language of the document, which originally assigned Congress the power to “make war.” According to Madison’s notes, “make” was changed to “declare,” “leaving to the Executive the power to repel sudden attacks.”
Decade after decade, the modern Congress has allowed its authority to be eroded, with only tiny and largely ineffective peeps of protest. In 1989, after the Panamanian General Manuel Noriega refused to honor election results, President George H. W. Bush ordered thousands of troops to Panama to, among other things, capture Noriega to stand trial for drug trafficking in the United States. In 1999, President Bill Clinton instituted an air campaign, joined by NATO allies, to stop ethnic cleansing in Kosovo; the operation continued beyond the sixty-day deadline to obtain congressional approval for introducing U.S. troops into hostilities imposed by the 1973 War Powers Resolution. In 2011, President Barack Obama launched missile attacks against military sites in Libya; Obama called the action “a limited and well-defined mission in support of international efforts to protect civilians and prevent a humanitarian disaster.” During Trump’s first term, he conducted air strikes against a Syrian airfield in 2017, and again in 2018 on chemical-weapons facilities, the second time joined by the United Kingdom and France. In 2021, President Joe Biden, invoking his constitutional authority as Commander-in-Chief, ordered “defensive” air strikes against Iranian-backed militias in Iraq and Syria.
These actions were typically abetted by legal opinions issued by the Justice Department’s Office of Legal Counsel; each opinion built on its predecessor to justify increasingly elastic interpretations of Presidential power. Jack Goldsmith, a Harvard law professor and a head of that office under President George W. Bush, has observed that the O.L.C. opinions on Presidential use of force “are famously promiscuously permissive.” The first part of O.L.C.’s analysis is whether the planned military activity furthers a “sufficiently important national interest.” Somehow, it always does. The second part is whether the “nature, scope and duration” of the expected use of force rises to the level of “ ‘war’ in a constitutional sense.” Somehow, it never does.
In considering whether military action amounts to a war, the O.L.C.’s lawyers examine factors such as whether there will be ground troops, the likely number of casualties, the scope of the mission (for instance, targeted strikes versus regime change), and the risk of escalation. As a report by the Congressional Research Service summarized, “The executive branch has never publicly concluded that a military operation crossed the threshold into an unconstitutional war, but it has opined that a variety of military operations do not reach this level. For example, O.L.C. concluded that deployments of 20,000 ground forces, a two-week air campaign including 2,300 combat missions, and an air campaign involving over 600 missiles and precision-guided munitions did not amount to wars in the constitutional sense.” Adding insult to congressional injury, “even when Congress enacted authorizations for use of military force—including in the Vietnam War, Persian Gulf War of 1991, post-September 11 conflict of Afghanistan, and the 2003 Iraq War—each Presidential Administration claimed that they possessed independent constitutional authority to engage in those conflicts even if Congress had not authorized them.” When Trump, in 2020, ordered the targeted killing of the Iranian general Qasem Soleimani while Soleimani was on a trip to Baghdad, the O.L.C. stretched the 2002 Authorization for Use of Military Force in Iraq to justify the killing of the Iranian leader. The O.L.C.’s interpretations are also, for the most part, unchallengeable. Since at least the war in Vietnam, courts have refused to referee disputes between the President and Congress over war powers.
In other words, Trump took office for the second time with few significant constraints on his power to deploy the military. Then, typically, he blew through whatever limits remained. The first strike on Iran, in June, 2025, stretched the limits of his authority because of the risk it posed of setting off a regional conflict. The January, 2026, operation to seize the Venezuelan President, Nicolás Maduro, pressed the limits even further; the closest analogy is the George H. W. Bush Administration’s capture of Noriega, but, in that case, Panama’s Defense Forces had killed a U.S. marine, and its National Assembly had declared a state of war with the United States. The current war with Iran—as Trump himself has described it—represents an even greater leap into a realm of unchecked Presidential power. If there is any practical restraint on unilateral Presidential action, it is hard to discern. The Framers would have found this chilling.
I spoke about the Iran war recently with Tess Bridgeman, who was a deputy legal adviser to the National Security Council during the Obama Administration; she is now a senior fellow and visiting scholar at N.Y.U. Law School’s Reiss Center on Law and Security and co-editor-in-chief of the website Just Security. Bridgeman told me that, prior to the Trump Administration, “this would have been one of the paradigmatic cases of, Of course you have to go to Congress.” Under previous Presidents, she said, “the separation of powers has been eroded. This is it being eviscerated.”
The War Powers Resolution of 1973 states that, within forty-eight hours of troops being introduced into hostilities, the President must inform Congress. The Trump Administration did so on Monday, asserting that the “strikes were undertaken to protect United States forces in the region, protect the United States homeland, advance vital United States national interests . . . and in collective self-defense of our regional allies, including Israel.” The law gives Congress the ability—in theory, anyway—to halt military action. In practice, this is doomed to failure in the current Congress; any resolution would have to survive an almost certain Presidential veto. Still, Congress taking a vote is important as a matter of symbolism and, not incidentally, politics. As Senator Tim Kaine, a Democrat who has been a stalwart defender of congressional prerogatives, put it, “Nobody gets to hide and give the President an easy pass or an end run around the Constitution. Everybody’s got to declare whether they’re for this war or against it.” In an effort to stop military action in Iran, Kaine, alongside the Republican senator Rand Paul, put forward a new war-powers resolution that has not been approved by Congress; it failed in the Senate on Wednesday, by a vote of 47–53; the House is expected to take up a similar measure on Thursday, with the same outcome expected.
In the meantime, the war shows every sign of widening. On Tuesday, a U.S. submarine torpedoed an Iranian warship near Sri Lanka, more than two thousand miles from Iran; Secretary of Defense Pete Hegseth said that it was the first such action since the Second World War. Hegseth vowed “death and destruction from the sky all day long” and said that the conflict had “only just begun.” If this is not “war in a constitutional sense,” nothing is. ♦