Defense Secretary Pete Hegseth told lawmakers Tuesday that President Trump does not need congressional authorization to resume military operations against Iran, asserting that existing executive authority is sufficient for whatever action the president chooses to take.
Said Hegseth: "Senator, our view is that should the president make the decision to recommence, that we would have all the authorities."
The claim is not a legal novelty — it is the latest installment in a 75-year project of executive branch expansion over the war power. But the setting matters: a cabinet secretary telling a sitting senator, on the record, that her chamber is simply not a necessary party to a decision about war.
Article I, Section 8 of the Constitution is unambiguous in assignment: Congress declares war. The Founders placed that power in the legislature deliberately, having watched English monarchs drag the country into continental conflicts on their own initiative. James Madison, writing to Thomas Jefferson in 1798, called the war power “the true nurse of executive aggrandizement” — the one power most in need of legislative check.
For roughly 150 years, that assignment held in practice as well as text. Congress declared war in 1812, in 1846, in 1898, in 1917, and in 1941. The declarations were sometimes hasty, sometimes manipulated by executive branch pressure, but they happened.
The rupture is precisely datable. In June 1950, President Truman committed U.S. forces to Korea without a congressional declaration, relying instead on a UN Security Council resolution. He did not ask Congress. Congress did not demand to be asked. The precedent was set: major armed conflict could begin and continue by executive will alone.
Congress attempted a structural correction after Vietnam. The War Powers Resolution of 1973, passed over Nixon’s veto, required the president to notify Congress within 48 hours of committing forces and mandated withdrawal after 60 days absent congressional authorization. Every president since Nixon — Republican and Democrat — has treated the Resolution as an advisory document they are free to ignore, and courts have largely declined to force the issue on standing grounds.
What is notable about Hegseth’s posture is not that it claims executive primacy — that is now the bipartisan default position of the executive branch. What is notable is the casualness of the dismissal and the specific political context.
Senator Lisa Murkowski has been exploring requiring an Authorization for Use of Military Force (AUMF) before any resumed strikes on Iran. That is a straightforward exercise of Congress’s Article I function. Hegseth’s response — that the administration already has all the authority it needs — forecloses the conversation before it begins.
The administration is simultaneously conducting, or threatening to resume, military operations in a country — Iran — with which the United States has no current AUMF on the books. The 2001 AUMF covers al-Qaeda and associated forces. The 2002 AUMF covered Iraq. Neither covers the Islamic Republic of Iran as a state actor.
Each administration that expands the unilateral war power makes the next expansion cheaper. The cost of Truman’s Korea precedent was paid by Johnson in the Gulf of Tonkin. The cost of the post-2001 AUMF expansions is being paid now, when a Defense Secretary can sit before the Senate and decline to identify any congressional role in a potential war with a nuclear-threshold state.
Murkowski’s effort deserves attention not because it is likely to succeed — the Senate Republican conference has shown little appetite for constraining this president on national security — but because it represents one of the few remaining institutional assertions that the legislature exists as a coequal branch. Whether that assertion can survive the current administration’s systematic indifference to constitutional structure is the question the 2025-2026 Congress will answer, largely by its silence.