PERSONAL REFLECTION -- Majestic blue skies greeted me as I turned into the Pentagon’s North Parking lot on Tuesday morning, September 11, 2001. As I made my way into work, I was thinking less about what the day might bring—life as a Joint Staff action officer could often feel like Groundhog Day—and more about the beautiful fall morning.
Less than three hours later, I would leave the Pentagon emerged in a profoundly different world, greeted by billowing black smoke rising into that same blue sky after American Airlines Flight 77 struck the building.
It became the most consequential day of my life—one that shaped my actions, my career, and my thinking ever since.
Twenty-five years later, I recall particular moments: the smell of smoke as we evacuated, the morgue erected to identify the victims, the fire burning through the Pentagon roof and the heroic firefighters who battled to extinguish it, and the enormous American flag unfurled across the Pentagon on September 12—a symbol of mourning, resolve, and national unity.
What forever remains with me is the memory of leaving the Pentagon that morning and the questions that haunted me:
How could we have missed this? How could our intelligence community and national security leaders have failed to protect the nation? How had we failed to connect the dots? How could we have suffered what the 9/11 Commission would later describe as a “failure of imagination?”
As with most intelligence failures, the warning signs appear painfully obvious in hindsight. The 1993 bombing of the World Trade Center demonstrated the potential consequences of a major terrorist attack on American soil. Osama bin Laden and the World Islamic Front openly declared war against Americans in 1998. That same year, al Qaeda bombed U.S. embassies in East Africa. In 2000, terrorists attacked the USS Cole in Yemen, killing 17 American sailors.
Individually and collectively, these events should have raised our level of concern and preparedness. They did not. We failed.
Looking back, I believe the roots of that failure can be traced to three areas: a lack of vigilance, poorly developed and undervalued partnerships, and an inadequate understanding of al Qaeda.
Intelligence failures—from Pearl Harbor to the 1973 Yom Kippur War to 9/11—often begin with a failure of vigilance. Nations minimize threats, overestimate their own capabilities, or explain away indicators because they do not fit prevailing assumptions. Warning signs are interpreted through the lens of what leaders believe an adversary is likely to do rather than what it may actually be capable of doing.
The 9/11 Commission’s finding of a “failure of imagination” captured a glaring weakness. But imagination in national security begins with discipline: examining vulnerabilities, challenging assumptions, developing mitigations, and running down leads even when they do not conform to conventional thinking.
Perhaps hubris played a role. A decade after winning the Cold War, the United States stood as the world’s preeminent power. That success may have contributed to a belief that our homeland was largely beyond the reach of a foreign adversary. Our guard was down. The result was the deadliest terrorist attack in American history.
September 11 also exposed serious weaknesses in our government’s ability to build and employ partnerships. Across the interagency, intelligence remained too often stove-piped. Agencies approached difficult problems through the narrow lens of their own authorities and responsibilities, creating seams an adaptive adversary could exploit.
Those seams were especially dangerous at the boundary between foreign intelligence collection and domestic law enforcement. Information held by one agency did not always reach another. Opportunities for integrated analysis were missed. We had capable organizations staffed by dedicated professionals, but too often they operated within separate cylinders of responsibility rather than as parts of an integrated national security enterprise.
Al Qaeda exploited those seams.
Perhaps most sobering was how little we understood about the enemy we suddenly faced. The attacks of September 11 were not al Qaeda’s opening act. The organization had already demonstrated its intent and capability through the 1998 embassy bombings in East Africa and the 2000 attack on the USS Cole. Yet after 9/11, it quickly became apparent how we were limited in our collective understanding.
Strikingly, among the first circulated materials on al Qaeda that I encountered after the attacks was a Defense Intelligence Agency analyst’s handbook describing the tactics, techniques, and practices of Osama bin Laden and his followers. I remember senior leaders on the Joint Staff asking for copies and acknowledging how little they knew about the organization.
Our adversary had studied us in extraordinary detail. We had not studied our adversary with the same intensity. We were, in important respects, blind to a deadly threat.
Today, remembrance alone is not enough.
The American philosopher George Santayana famously warned: “those who cannot remember the past are condemned to repeat it.”
Remembering September 11 must mean more than recalling where we were, honoring those who died, or recounting the heroism that followed. It must mean examining whether we have truly absorbed the lessons purchased at such extraordinary cost.
The first lesson is vigilance. Today’s threats may emerge in cyber, space, artificial intelligence, biotechnology, terrorism, or domains we have yet to fully appreciate. Vigilance demands healthy skepticism about our own capabilities and respect for those of our adversaries. It requires leaders willing to challenge comfortable assumptions and recognize weak signals before they become catastrophic warnings.
The second lesson is partnership. Public-private partnerships are now foundational to understanding many threats confronting the nation, particularly in cybersecurity and critical infrastructure. But partnerships cannot become static arrangements or bureaucratic slogans. We must continually reassess relationships across government, industry, and our allies, asking whether they provide meaningful access, insight, speed, and competitive advantage.
The third lesson is understanding the adversary. Our limited understanding of al Qaeda before September 11 should force us to ask a difficult question today: Which adversary are we underestimating now? Where are our greatest knowledge gaps? Which emerging tactics, technologies, organizations, or intentions are we explaining away because they do not fit our assumptions? Who is studying us more carefully than we are studying them?
These questions should make us uncomfortable.
On September 11, 2001, nearly 3,000 people began an ordinary morning never imagining what would follow. For those of us who experienced that day from inside the Pentagon, the memories remain deeply personal. But the responsibility to learn from that day belongs to all of us—especially those entrusted with our nation’s security.
As we honor those who lost their lives, we should do more than look backward. We should reflect on where we failed. We should remember what complacency cost us. And we should renew our commitment to vigilance, partnership, and understanding—so that the lessons of September 11 are never again learned only after tragedy strikes.
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