Twenty-five years ago, members of the jihadi group al-Qaeda hijacked four American airplanes, flying two of them into the World Trade Center towers in New York City and one into the Pentagon, in Washington, D.C. Passengers attempted to seize control of the fourth plane, and it crashed in Shanksville, Pennsylvania, killing everyone aboard. The hijackers killed 2,977 people in total—by far the deadliest single terrorist attack in history. To many Americans, the events of September 11, 2001, seemed to come out of nowhere. Few had even heard of al-Qaeda before the attacks. Yet by September 12, the United States had plunged into what President George W. Bush called “a war against terrorism,” a fight that would persist for decades, ensnare multiple jihadi groups, and extend to all corners of the earth.

The United States had many setbacks in this war. The ways in which it attempted to prevent another 9/11, or an even larger-scale attack, entailed massive, often inefficient investments as well as troop losses. Some of its efforts, such as the full-scale wars in Afghanistan and Iraq, were brutally destructive. The 2003 invasion of Iraq, in particular, drove a surge in jihadi recruitment. In the years since 2001, various new jihadi groups—some of them connected to al-Qaeda, some opposed to it—have set up shop in the Middle East and across East and West Africa, where they have fueled bloody civil wars, shattered local communities, and launched terrorist attacks both in the region and outside it.

But the war on terrorism has not been a complete failure, either. Al-Qaeda itself is devastated. There have been few jihadi attacks on U.S. territory—perhaps the most important measure of success for most American leaders—in the past two and a half decades. According to New America Foundation data, jihadi terrorists have killed 122 people in the United States since 2001, a fraction of what U.S. officials feared in the aftermath of 9/11. And although jihadi groups survive, jihadism has lost much of its ideological salience.

Consider what has happened since 2023. On October 7, Hamas, a group that al-Qaeda regularly criticized for compromising on theological principles in the pursuit of its political agenda, launched a bloody terrorist attack on Israel, killing more than 1,100 people. Israel went on to kill tens of thousands of Palestinians in Gaza, many of them civilians, and conduct other attacks in Iraq, Lebanon, Syria, and the West Bank. In 2025, the United States joined Israel in bombing Iran, and in 2026 the United States and Israel launched a full-scale war with the initial objective of regime change in Tehran. The Israeli war in Gaza led to mass protests around the world, and all of these events offered fodder for conspiracy theories about the enemies of Islam plotting against Muslims. Yet in contrast to the 2003 U.S. invasion of Iraq or the onset of the Syrian civil war in 2011, they have triggered no jihadi surge. Indeed, the former jihadis who overthrew the Syrian dictator Bashar al-Assad, in 2024, quickly sought to make nice with states that have long fought terror organizations, including the United States and Saudi Arabia, upon taking power.

A quarter century after Osama bin Laden gave the order for the 9/11 attacks, his successors have not built a durable transnational movement capable of repeatedly attacking the United States and forcing governments to bend to their demands. The sense of historic possibility that once made the jihadi movement so threatening to Western countries has faded. The United States may not have won the war on terrorism, but the jihadis clearly lost.

THE BIRTH OF A MOVEMENT

In late 2001, al-Qaeda appeared ascendant. The movement grew out of the armed struggle against the Soviet occupation of Afghanistan in the 1980s, and it attracted Muslim fighters from around the world. Under bin Laden’s leadership, al-Qaeda had many goals, including helping the Taliban secure power in Afghanistan and training its members for terrorist and insurgent campaigns throughout the Muslim world, but ousting the United States from the Middle East was at the top of the list. Other jihadis prioritized fighting governments that they saw as foreign invaders in Chechnya and Kashmir, toppling supposedly apostate Arab regimes, battling Shiite Muslims, or creating a caliphate.

The scale of its attack on the United States gave al-Qaeda an aura of momentum and outsize influence within the jihadi movement and beyond. After 9/11, the movement grew in stature, and fighting the United States and its Western allies, which most jihadis had previously considered a relatively low priority, became a more mainstream objective. The fact that the U.S. government would make few distinctions between al-Qaeda-linked groups and jihadis with a more local focus in its subsequent counterterrorism campaign only reinforced that trend.

Several factors had made the 2001 attacks possible. Among them were the many shortcomings in Washington’s approach to counterterrorism, including the mistakes identified by the 9/11 Commission, an independent body set up by the U.S. government in 2002, on which I served as a staff member. Those included poor information sharing among U.S. government agencies, a failure to place on watchlists future hijackers who were suspected of links to al-Qaeda and were believed to be traveling to the United States, a lackadaisical effort to find suspected terrorists believed to be in the United States already, and no response to alarming field officer reports that........

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