The scale of Israel’s intelligence failure—why the Israeli government did not act more preemptively on at least one known intelligence warning—is almost as shocking as the brutality and success of the Hamas attack itself on October 7. As the Israel Defense Forces expand their ground incursion into Gaza, and with the death toll in the ensuing war already in the thousands, it is not premature to reflect on the specific missteps that made “Israel’s 9/11” possible. A full reckoning will require months if not years of investigation but as scholars of terrorism, armed conflict, and political science, we highlight three potential major intelligence failures that any intelligence investigation should focus on to learn from this failure.

As Amy Zegart points out, major surprise attacks are “almost never really surprises.” Such appears to be the case with the October 7 attack. On October 9, Egyptian intelligence said publicly that it had given Israel repeated high-level warnings of a pending attack—“something big”—before the Gaza-based Hamas struck, including a direct phone call from Cairo’s intelligence minister to Prime Minister Benjamin Netanyahu in late September. US intelligence also warned its own policymakers of unusual Hamas activity and of a general increased threat from Hamas based on multiple streams of intelligence, including information that it received from Israel—though reports notably did not include any tactical details. It is difficult to understand what prevented Israeli security forces from acting. Israeli security officials probably made three critical mistakes.

A Dated Picture of Hamas Capabilities and Intentions

Israeli leaders almost certainly believed Israel’s military superiority would be able to repel any attack from paramilitary forces. In turn, this led to complacency, assuming Hamas would not launch a major attack because Hamas could not defeat Israel. As Amos Yadlin, the former Israeli chief of military intelligence, notes, Netanyahu appears to have convinced himself that “Hamas is not that dangerous, we can live with it. Every three, four years, we’ll do a round of exchange of fire. But this is not the most dangerous enemy of Israel.” If true, this was a fatal miscalculation. In an echo of the 1973 intelligence failure that led Israel to be surprised by Arab attacks initiating the Yom Kippur War, Israel miscalculated both Hamas’s capabilities and its intentions—and its own defense capability.

Underestimating Hamas’s Capabilities

In 1973, Israel did not to respond to intelligence warnings that attacks from its Arab neighbors were imminent. Because Arab militaries had previously performed poorly, Israel assumed that it could block any assault and its enemies would be deterred by Israel’s military superiority. A similar logic regarding Hamas may have spread within the current Israeli security apparatus. Yes, Hamas’s military wing had launched many terrorist attacks in Israel since the 1990s, but none demonstrated the organization or capability needed to conduct an attack as sophisticated as it did on October 7. However, Israeli leaders and other observers have been well aware that Tehran had been increasing aid to support Hamas for years. Israel nevertheless very clearly underestimated how much such resources boosted Hamas’s current military capabilities and command and control.

Misunderstanding Hamas’s Intentions

Hamas intentions may have been, and may still be, severely misunderstood. Israeli leaders may have calculated that Hamas would not wage such an attack in part because Israel was providing economic incentives for peace (namely, by overseeing the transfer of Qatari funding to Gaza). Israel may have come to believe that Hamas’s intentions had softened, or that Hamas could be contained without progress toward a two-state solution. Hamas leaders such as Ismail Haniyeh and Khaled Meshal between 2006 and 2014 expressed openness to an indefinite truce (hudna) with Israel under a two-state solution based on 1967 borders. It isn’t clear they really meant it, and since then there was no progress toward a two-state solution. More importantly, permanent peace with Hamas could not and cannot be bought; research on actors with “sacred values” such as Hamas militants shows that material incentives for peace backfire and invoke moral outrage.

For Hamas, accommodation with Israel was clearly tactical (short-term), not strategic (long-term). As Bruce Hoffman points out, Hamas’s genocidal intentions have never been a secret, but are baked into its “DNA”—its 1988 founding covenant and the group’s revised 2017 charter. Almost two decades ago, in his classic Inside Terrorism (2006), Hoffman identified Hamas as a religious terrorist group with an antisemitic and millenarian mission of jihad to destroy Israel and kill Jews. Hamas’s rise since the 1990s represents the “Islamization of the Palestinian-Israeli conflict.” Since then, a secular-nationalist conflict has morphed into a religious one. Recent research by Monica Duffy Toft (aided by one of us) shows that conflicts where religion is central (as has been the case with Hamas) are deadlier and less likely to end in durable peace.

Rather than peace, it is likely that Hamas (and its backers in Iran) wanted war, anticipating a major Israeli military response to its October 7 attack, which it could weaponize in information war against the Israelis to gain sympathy for the Palestinian cause internationally and erode support for Israel. On the eve of October 7, Hamas was increasingly isolated. Domestically, only 29 percent of Gazans expressed trust in the Hamas government and only 24 percent said they would vote for Ismail Haniyeh over Mahmoud Abbas or a rival Fatah candidate, according to a recent Arab Barometer survey. Internationally, the Palestinian cause was being sidelined as a result of the Abraham Accords. As Audrey Kurth Cronin points out, Hamas very likely wanted to provoke an overreaction by Israel that would impair Arab-Israeli “‘normalization’ in the Middle East,” including the ongoing US-brokered talks for a Saudi-Israeli peace deal that had made progress in 2023. Israeli leaders underestimated how committed Hamas was to reversing its diplomatic isolation.

Tricked by Hamas’s Denial, Deception, and Improved Operational Security

Denial and deception activities seek to mislead intelligence operations, including by adulterating intelligence channels with disinformation. Hamas did just this in at least two identifiable ways. First, according to one Israeli source, Hamas deceived Israel by giving “a public impression that it was not willing to go into a fight or confrontation with Israel while preparing for this massive operation.” Second, Hamas used improved operational security tactics. Intelligence shared with the United States indicates that a small cell of Hamas operatives communicated for two years via hardwired phones embedded in the network of tunnels underneath Gaza; this group reportedly avoided using cells phones and computers in order to evade detection. This denied collection by Israeli intelligence officials. As a result, Hamas apparently was able to prepare the October 7 attack in secret without arousing Israeli suspicions.

Confirmation Bias and Hamas Preparations for War

If it took years to plan the October 7 attack, as appears the case, how did no one notice? Despite Hamas’s denial and deception activities and improved operational security, there were some troubling indicators. Why were they dismissed? One likely culprit is confirmation bias, leading intelligence analysts “to undervalue or ignore evidence contradicting an early judgment and value evidence that tends to confirm already held assessments.” For example, a CNN investigation analyzed propaganda video and satellite imagery that showed expansion of and increased activity at multiple Hamas training camps in Gaza over the past two years. When questioned, an Israel Defense Forces spokesperson claimed the findings were “nothing new.” This suggests Israeli analysts saw what they had seen before—training that did not signal a catastrophic event. One cannot help but wonder how dark the clouds were before the storm.

Many questions remain, requiring after-action reviews and an investigation similar to that conducted by the 9/11 Commission to fully analyze these intelligence and security failures. But there are certainly lessons to be learned—not just for the Israeli intelligence and security apparatus but for intelligence services globally. Countering terrorism requires intelligence agencies to confront biases, fight complacency, and think creatively regarding the evolving nature of terrorist attacks and how, when, and why terrorist organizations will deploy a range of tactics in the future.

Haleigh Bartos is an associate professor of the practice in CMIST at Carnegie Mellon University. She has fifteen years of experience working to support policy and studying national security. She teaches courses on policy writing and national security at CMU, including Writing for Political Science and Policy, Terrorism in Sub-Saharan Africa, and In the News: Analysis of Current National Security Priorities.

John Chin is an assistant teaching professor of political science in CMIST at Carnegie Mellon University. He is the lead author of an Historical Dictionary of Modern Coups D’état (2022). He has published in top political science journals, most recently a coauthored article in the Texas National Security Review on “Understanding National Security Strategies Through Time.”

The views expressed are those of the authors and do not reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense.

Image: Damage to house from Hamas rocket fire in 2012 (credit: Israel Defense Forces)