Three days after 9/11

Congress passed the Authorization for Use of Military Force on September 14, 2001 — three days after the September 11 attacks. The vote was 420-1 in the House and 98-0 in the Senate. The text was 60 words long.

The authorization permitted the President to use “all necessary and appropriate force against those nations, organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons.”

The substance of the authorization was the response to a specific attack by a specific organization (al Qaeda) operating with the support of a specific government (the Taliban regime in Afghanistan). The text was framed accordingly: against those responsible, and against those who harbored them.

Twenty-four years later, four administrations have used the 2001 AUMF to authorize military operations against:

• al Qaeda in Iraq, Yemen, Pakistan, Somalia, the Philippines
• The Islamic State (ISIS) — an organization that did not exist on September 11, 2001
• Al-Shabaab in Somalia
• Al Qaeda in the Arabian Peninsula
• Various successor and affiliate organizations across more than a dozen countries

Most of these targets had no operational connection to the 9/11 attacks. Many did not exist when the AUMF was passed. The “harbored” language has been read to extend to governments and organizations whose connection to the original target organizations is, in some cases, attenuated to the point of disappearance.

The 2002 AUMF

The Authorization for Use of Military Force Against Iraq Resolution of 2002 was a separate statute, authorizing force against the government of Iraq under Saddam Hussein. The Iraq War operations it authorized ended in 2011 (in a formal sense — US forces returned in 2014 to operate against ISIS, but those operations have been conducted under the 2001 AUMF).

The 2002 AUMF, despite the underlying conflict ending years ago, remains technically in force. It has been cited periodically in legal arguments to support military operations whose primary authority is contested.

The 1991 AUMF

The Authorization for Use of Military Force Against Iraq Resolution of 1991 — for the Gulf War — also remains technically in force. The Gulf War operations it authorized ended in 1991. The authorization has been cited in subsequent legal arguments around Iraq-related operations.

What stale AUMFs actually do

The substantive concern with stale AUMFs is structural. Congressional war authority is at the heart of the constitutional design. Article I gives Congress the power to declare war and to raise and support armies. Article II gives the President command authority over the armed forces in their actual operations.

The pattern of stale, broadly interpreted AUMFs collapses this distinction. The executive branch can argue that operations against new targets, in new locations, are authorized by a 24-year-old statute that did not contemplate the targets and did not name the locations. The argument is sometimes legally defensible in narrow cases; in the aggregate, it has produced an executive-branch war-making authority that Congress has not specifically approved.

Reform proposals address this:

Sunset. AUMFs should expire on a defined timeline (e.g., five years), forcing reauthorization rather than indefinite extension.

Specificity. AUMFs should name the specific target organizations or governments. New targets require new authorization, not stretched interpretation.

Geographic limits. AUMFs should specify the countries or regions in which operations are authorized, requiring expansion to be explicit rather than implicit.

Reporting requirements. Substantial executive-branch reporting on operations under AUMFs, with regular congressional review.

The political alignment

AUMF repeal has produced unusual bipartisan alignment in recent sessions. Senator Tim Kaine (D-VA) and Senator Todd Young (R-IN) have been among the leading advocates for repeal of stale AUMFs in the Senate. The 2002 AUMF repeal has had bipartisan majorities in both chambers of Congress in multiple sessions.

The 2002 AUMF repeal advanced through the Senate in 2023 with substantial bipartisan support. The political coalition behind repeal has included libertarian-leaning Republicans concerned about executive war power, traditional foreign-policy moderates concerned about congressional abdication, and most Democrats. The opposition has come primarily from senators concerned about flexibility for executive-branch operations and from those concerned that repeal would constrain ongoing operations against ISIS or al-Shabaab.

The 2001 AUMF repeal has been harder. The 2001 AUMF is the legal basis for ongoing operations in multiple theaters. Repeal without a replacement framework would create a legal vacuum for those operations. Repeal with a replacement framework requires consensus on the replacement — which has proven elusive.

The replacement framework

A replacement AUMF would, in most serious proposals, include:

Identified target organizations. Specific named groups with operational connection to current concerns, not the 2001 framework’s “those who harbored them.”

Geographic scope. Specific countries or regions, with expansion requiring affirmative congressional action.

Sunset. Five-year or shorter expiration, with reauthorization required for continuation.

Robust reporting. Substantial executive-branch reporting on operations, target lists, civilian casualties, and strategic objectives.

Civilian harm protection. Specific provisions on civilian-protection standards and oversight of incidents.

Restrictions. Geographic, target-class, and operation-type limits that the 2001 AUMF has been read past.

The Kaine-Young replacement proposals have included variants of these elements. None has yet cleared both chambers.

What’s stalled the broader effort

Several factors:

Implementation complexity. Replacing the 2001 AUMF requires consensus on operations that span multiple theaters, multiple agencies, and multiple administrations of differing political character. Each administration has its own preferences about flexibility versus constraint.

Executive branch resistance. The executive branch (across both parties’ administrations) has generally opposed sharply constraining AUMF replacement. The institutional preference is for broader authority.

Legislative bandwidth. AUMF reform competes with other legislative priorities for floor time and political capital. It tends to advance when adjacent foreign-policy crises raise its salience.

Specific operations. Operations against specific groups (al-Shabaab, AQAP, ISIS) create constituencies — both supportive (continued operations) and constraining (targeted critics) — that complicate a clean reform.

What to watch

• 2002 AUMF repeal completion. Senate has acted; House action remains pending across sessions.
• 2001 AUMF replacement framework. Kaine-Young-style proposals; reintroduction expected.
• Specific operations authorization. Periodic War Powers Resolutions targeting specific operations (Yemen, Iran-related, others).
• NDAA-attached reforms. AUMF reform has occasionally advanced through National Defense Authorization Act vehicles when standalone movement has stalled.
• Civilian casualty data and reporting. Ongoing implementation of recent reforms; affects political environment for AUMF debate.

Bottom line

The 2001 and 2002 AUMFs are among the most consequential examples of legislation that has outlived its original purpose while continuing to authorize substantial executive action. Repeal has bipartisan support in principle and has produced substantial movement in recent sessions. The political and institutional resistance has been substantial enough that repeal has not yet been completed. The work of restoring congressional war authority is, like most structural reform, slow and unromantic — and important in proportion to the constitutional commitments involved.