Authorization for Use of Military Force of 2001

Based on Wikipedia: Authorization for Use of Military Force of 2001

The Sixty Words That Shaped Twenty-First Century War

One woman stood alone.

On September 14, 2001, just three days after the towers fell, the United States Congress voted on a resolution that would reshape American warfare for decades to come. In the Senate, ninety-eight members voted yes. In the House, four hundred and twenty voted yes. Exactly one person—Representative Barbara Lee of California—voted no.

Lee wasn't opposed to responding to the attacks. She was terrified of something else: the words on the page. The resolution she voted against contained sixty words that granted the president authority to wage war against anyone, anywhere, for as long as he deemed necessary. She saw it as a blank check. She would spend the next two decades trying to cancel it.

She was right to be worried.

What the Authorization Actually Says

The Authorization for Use of Military Force—usually called the AUMF, pronounced "awe-muff"—became law on September 18, 2001. Its core grant of power fits in a single paragraph. The president is authorized to use "all necessary and appropriate force" against nations, organizations, or persons that he determines planned, authorized, committed, or aided the September 11 attacks, or harbored those who did.

Notice the word "determines." The president decides who qualifies. Not Congress. Not the courts. The president.

Notice also what's missing: any geographic limitation. The law doesn't mention Afghanistan. It doesn't mention any country. It doesn't require the targets to be governments. Individuals count too.

This is fundamentally different from a formal declaration of war. When Congress declares war—as it did against Japan in 1941—the president gains access to the full arsenal of wartime powers: seizing property, detaining enemy aliens, censoring communications. A declaration of war is an all-or-nothing switch that transforms the entire country onto a war footing.

The AUMF is something else. It's what lawyers call a "statutory authorization of force"—a permission slip for military action that keeps certain limits in place. The president can use military force, but he can't necessarily exercise all the domestic powers that come with a declared war. At least, that's the theory.

The Rejected Draft

What's remarkable is how much worse it could have been.

The initial draft of the resolution contained language authorizing the president to "deter and preempt any future acts of terrorism or aggression against the United States." Members of Congress recognized immediately what this would mean: unlimited authority to attack anyone, anywhere, at any time, based on nothing more than the administration's assessment that they might someday pose a threat.

That language was stripped out. Congress explicitly rejected preventive war authority. The final version limited force to those connected to the September 11 attacks—the attacks that had already happened, not hypothetical future ones.

This distinction would matter enormously in the years to come, though not in the way Congress intended.

Barbara Lee's Lonely Vote

Barbara Lee had been in Congress for less than three years when she cast the only no vote. She had grown up in Texas, served as a congressional staffer, and won her seat in a special election in 1998. Nothing in her background marked her as a likely dissenter from a moment of national unity.

Her objection wasn't to military action itself. She believed a response was necessary. What frightened her was the vagueness of the authorization. She saw a parallel to the Gulf of Tonkin Resolution of 1964, which had authorized "all necessary measures" in Southeast Asia and led to years of undeclared war in Vietnam.

"It was a blank check to the president to attack anyone involved in the September 11 events—anywhere, in any country, without regard to our nation's long-term foreign policy, economic and national security interests, and without time limit," she said at the time.

The comparison to Tonkin was apt. That resolution had been passed in response to a specific incident—naval skirmishes in Vietnamese waters—but its broad language enabled a decade of escalating warfare that Congress never explicitly authorized. Lee worried the AUMF would follow the same trajectory.

For years afterward, Lee received death threats. She needed a police escort. But she kept her seat, kept winning reelection, and kept introducing legislation to repeal the authorization she had voted against. She would try multiple times to revoke it before leaving the House in 2025 after an unsuccessful Senate bid.

The Expanding Interpretation

Here is where Lee's warnings proved prophetic.

The AUMF was written in response to al-Qaeda's attacks. Al-Qaeda was based in Afghanistan, protected by the Taliban government. The connection was direct and obvious. Within weeks, American forces were on the ground in Afghanistan pursuing the people who had planned September 11.

But administrations soon began reading the sixty words more creatively.

The phrase "associated forces" started appearing in government documents. It's not in the AUMF. You can read the law front to back and you won't find it. But officials in the Bush, Obama, and Trump administrations used it to extend the authorization's reach far beyond Afghanistan and al-Qaeda proper.

The logic worked like this: if a group had some connection to al-Qaeda—shared personnel, shared ideology, shared enemies—then it was an "associated force" covered by the original authorization. Military action against such groups required no new congressional approval.

By December 2016, the Obama administration's Office of the President published an interpretation stating that the AUMF authorized force not just against al-Qaeda and the Taliban, but against other "militant groups" as well.

The full list of who the military believes it can target under the AUMF is classified. We don't know everyone on it.

A Geography of Forever War

The AUMF has been used to justify military operations in at least fourteen countries.

Afghanistan, obviously. But also the Philippines. Georgia. Yemen. Djibouti. Kenya. Ethiopia. Eritrea. Iraq. Somalia. Libya. Syria. And others. Between 2018 and 2020 alone, the United States initiated what it called "counter-terror" activities in eighty-five countries. Of those, the 2001 AUMF has been cited to authorize classified military campaigns in at least twenty-two.

Consider Somalia. The United States has been conducting military operations there for years under the AUMF, primarily targeting al-Shabab, a militant group that didn't exist when the September 11 attacks occurred. Al-Shabab formed in 2006, five years after the AUMF was passed. Its connection to the original authorization rests entirely on its later affiliation with al-Qaeda—an affiliation that made it, in the government's interpretation, an "associated force."

The Biden administration continued airstrikes in Somalia, supporting a local military unit called the Danab Brigade against al-Shabab. Senator Ben Cardin, a senior Democrat on the Senate Foreign Relations Committee, called this "inconsistent with the intent of Congress" and urged the administration to seek new authorization.

Other senators disagreed. Marco Rubio argued the president doesn't need congressional authorization "to target terrorists who are posing a threat to the United States, no matter where they are in the world."

This debate—whether the president needs permission or already has it—has continued for over two decades without resolution.

The Courts Weigh In

The judicial branch has occasionally pushed back, though not always successfully.

In 2006, the Supreme Court ruled against the Bush administration in a case called Hamdan versus Rumsfeld. The administration had cited the AUMF as authority for establishing military tribunals at Guantanamo Bay to try suspected terrorists. The Court disagreed. It found that the tribunals were illegal under both military justice law and the Geneva Conventions, and that the AUMF did not give the president authority to create them.

But in other cases, the AUMF has been successfully invoked. The Department of Justice cited it in defending the National Security Agency's warrantless surveillance program. Congress itself "affirmed" the president's detention authority under the AUMF when it passed the National Defense Authorization Act for 2012.

In 2016, Bruce Ackerman, a constitutional law professor at Yale, argued that the AUMF's use had expanded so far beyond its original text that it more closely resembled the rejected draft—the one with preventive war authority—than the version Congress actually passed.

The Strange Case of the Venezuelan Boats

In 2025, the AUMF surfaced in an unexpected context: the Caribbean.

The Trump administration cited the 2001 authorization to justify strikes against Venezuelan boats. Critics immediately pointed out a problem: drug smuggling is not terrorism, and the September 11 attacks had nothing to do with Venezuela. The connection to the original authorization was tenuous at best.

The administration's response was to deport survivors of one strike to other countries—a move that conveniently prevented them from challenging their treatment in American courts. Without detainees on American soil, there was no one with standing to sue.

This represented perhaps the furthest stretch yet of a law written in response to al-Qaeda's attack on New York and Washington.

The Failed Attempts at Repeal

Multiple efforts have been made to revoke or replace the AUMF. None have succeeded.

In 2017, Barbara Lee finally seemed to make progress. Her amendment to sunset the authorization within 240 days passed the House Appropriations Committee with support from both libertarian Republicans and Democrats. The idea was to force Congress to actually debate what it was authorizing—to make representatives go on record about which wars they supported.

The amendment was removed from the bill by the Rules Committee before it could reach the House floor. The AUMF survived.

In 2018, Senators Tim Kaine and Bob Corker proposed updates to the authorization. Nothing passed.

In 2023, a bipartisan group including Republicans Rand Paul, Mike Lee, Mike Braun, and JD Vance introduced the "End Endless Wars Act" to repeal the AUMF entirely. Rand Paul described the authorization as enabling "a worldwide war, all the time, everywhere, forever."

General Mark Milley, then chairman of the Joint Chiefs of Staff, had testified in 2021 that the 2001 AUMF was "the one we need to hang on to" and was "critical for us to continue operations."

The military wanted to keep it. Reformers wanted to end it. The status quo won.

Why It Persists

The AUMF's longevity is partly about political incentives. For presidents, it provides legal cover for military actions without the inconvenience of congressional debate. For members of Congress, it provides political cover too—they can criticize specific strikes without having to vote against authorizations that might make them look soft on terrorism.

It's also about institutional inertia. The law has been on the books for more than two decades. Entire careers in the military and intelligence agencies have been built around operations conducted under its authority. Revoking it would require answering difficult questions: Which operations would have to stop? Which ongoing missions would lose their legal foundation?

And there's genuine disagreement about whether repeal is wise. Some argue that terrorist threats remain real and that requiring fresh congressional authorization for each operation would hamstring effective response. Others counter that the Constitution explicitly gives Congress, not the president, the power to declare war—and that the AUMF has become an end-run around that fundamental allocation of authority.

The Tonkin Parallel

Barbara Lee invoked the Gulf of Tonkin Resolution when she cast her lonely vote. The parallel deserves examination.

The Tonkin Resolution was passed in 1964 after North Vietnamese patrol boats allegedly attacked American destroyers. Congress authorized the president to take "all necessary measures" to repel attacks and prevent further aggression in Southeast Asia. The vote was nearly unanimous: 88-2 in the Senate, 416-0 in the House.

What followed was the Vietnam War—years of escalating conflict, hundreds of thousands of American troops deployed, tens of thousands killed. Congress never declared war. The Tonkin Resolution provided the legal authority instead.

The resolution was finally repealed in 1971, but by then the war had taken on a life of its own. It continued until 1975.

The AUMF has now been in effect longer than America was in Vietnam. The war in Afghanistan, conducted under its authority, became the longest war in American history. And unlike the Tonkin Resolution, the AUMF shows no signs of repeal.

What the Constitution Says

Article One, Section Eight of the Constitution is clear: Congress has the power to declare war. This wasn't an accident. The founders deliberately took war-making power away from the executive. They had seen European monarchs plunge their nations into conflict on personal whim, and they wanted something different.

James Madison wrote that the executive branch is "most interested in war, and most prone to it," which is why the Constitution "with studied care vested the question of war in the Legislature."

But the Constitution doesn't define what counts as "war." And since World War II, Congress hasn't formally declared war even once—not in Korea, not in Vietnam, not in the Gulf, not in Afghanistan or Iraq. Instead, it has passed authorizations of force: permission slips that grant military authority without the full legal and political weight of a declaration.

The AUMF fits this pattern. It is war without being called war. It is authorization without clear limits. It is congressional permission granted once and never revisited.

The Present Moment

Today, more than twenty years after September 11, the Authorization for Use of Military Force remains in effect. It has been cited in connection with military actions across the globe. Its interpretation has expanded far beyond its original text. Its repeal has been attempted and failed multiple times.

The full list of groups and individuals the United States believes it can target under the authorization remains classified. Citizens cannot know the full scope of what their government is doing in their name under this law.

Barbara Lee is no longer in Congress. The authorization she opposed lives on.

Sixty words, written in grief and anger in the days after the worst terrorist attack in American history, continue to shape American foreign policy a quarter century later. Whether they will ever be revoked—and what would replace them if they were—remains one of the open questions of American governance.

One woman saw this coming. The other 420 members of the House did not. Or perhaps they did, and voted yes anyway.

History does not record which interpretation is correct.