The Iraq War is turning 20. And while Saddam Hussein is long gone, thousands of U.S. troops remain in Iraq — and the legal authorities underpinning the war remain on the books.
President Biden may have declared that our nation is no longer at war, but more than a speech is needed to end U.S. hostilities in the Middle East. Congress must reform the legal landscape to guard against the kind of military adventurism that has marked the past two decades.
The urgency of this task was made clear in 2020, by the Trump administration’s misuse of the Iraq War Authorization for Use of Military Force (“AUMF”) to attack and kill a top Iranian general, Qassem Soleimani. For a few short moments, the nation held its breath, wondering if it had been plunged into a new war with Iran. Congress rushed to pass a War Powers Resolution demanding the withdrawal of U.S. forces from hostilities with Iran and rejecting President Trump’s interpretation of the AUMF, but Trump vetoed the legislation.
These events invigorated congressional efforts to repeal the Iraq War AUMF. Repealing the AUMF would remove any veneer of congressional approval for hostilities in Iraq and would signal congressional disapproval of offensive hostilities with Iran. Lawmakers from across the political spectrum are now leading legislation to take the AUMF off the books: In the House, Rep. Barbara Lee (D-Calif.) has joined forces with Rep. Chip Roy (R-Texas). In the Senate, Sen. Tim Kaine (D-Va.) and Sen. Todd Young (R-Ind.) have pushed Majority Leader Chuck Schumer (D-N.Y.) to prioritize repeal.
This ongoing effort is an inspirational showing of bipartisanship — and if it succeeds, it will constitute a critical step toward ending hostilities in Iraq. But it is not enough.
When the Bush administration invaded Iraq, it relied at least as much on what President Bush claimed was his inherent “authority as Commander in Chief” as it did on the Iraq War AUMF. In announcing the invasion, President Bush said he was acting “pursuant” to his constitutional authority and only “consistent” with Congress’s enactment.
The assertion was striking. The Constitution gives Congress, not the president, the authority to declare war. It also gives Congress the power to create and regulate the military. Although the Constitution vests the president with an inherent authority to “repel sudden attacks” on U.S. territory and persons, nothing in its text or design suggests that a president may unilaterally initiate hostilities.
The Bush administration’s broad reading of constitutional authority, however, was no anomaly; Presidents Obama, Trump, and Biden have similarly encroached on Congress’s war powers. President Obama cited his constitutional authority, not an AUMF, as the original basis for hostilities against the Islamic State in Iraq and Syria. President Trump cited his constitutional authority, in addition to the Iraq War AUMF, as legal grounds for the 2020 strike on General Soleimani. And President Biden has contended that congressional authorization is not needed for his administration’s tit-for-tat hostilities against Iran-backed militias in Iraq and Syria, which he claims fall within his power to defend U.S. forces and foreign partners.
Indeed, there are ways in which the Biden administration has an even more capacious interpretation of presidential power than did the Bush administration. Since 2003, successive administrations have expanded and implemented controversial theories for when the president can use force without congressional authorization.
Presidents Obama and Trump stretched the “national-interest theory,” an executive branch-created doctrine under which the president may use force short of all‑out war to protect supposed national interests. Their administrations interpreted the doctrine to permit interventions in Muammar Gadhafi’s Libya; in Iraq after the declared end of the Iraq War; and in Syria after Bashar al-Assad’s use of chemical weapons — all without congressional authorization. The Biden administration inherited these interpretations.
President Biden himself has overseen a marked increase in invocations of “collective self‑defense,” a different executive branch-created doctrine under which the president may protect foreign militaries. Collective self-defense is now cited as the basis for U.S. hostilities in Somalia, conducted in “defense” of the Somali National Army on its “offensive operations” against al-Shabaab. Collective self-defense is additionally used to justify hostilities against Iran-backed militias in Iraq and Syria.
To end our era of endless war, Congress must resist these overbroad interpretations of the president’s authority.
That means passing resolutions rejecting the national-interest and collective self-defense theories, demanding the withdrawal of U.S. forces from unauthorized hostilities, and cutting off funding for wars that Congress has not explicitly approved.
It also means bolstering the War Powers Resolution — a 1973 law passed to prevent presidential war-making — through bipartisan legislation like the National Security Powers Act.
After 20 years, former advocates of the Iraq War acknowledge that the invasion was a tragic mistake. But without efforts to repeal the Iraq War AUMF and claw back Congress’s constitutional war powers, U.S. hostilities in Iraq and its neighbors will continue.
Katherine Yon Ebright is counsel in the Liberty and National Security Program at the Brennan Center for Justice at NYU Law. She is the author of the recent report “Secret War: How the U.S. Uses Partnerships and Proxy Forces to Wage War Under the Radar.”