# US intelligence failures preceding 9/11 attacks

> Live situation record from CLSTR: https://clstr.news/situations/us-intelligence-failures-preceding-911-attacks
> Updated: 2026-09-10T05:55:50.000Z. Sources: 8. Developments: 2.

Investigations into the September 11 attacks highlight significant intelligence failures within the CIA and FBI. Reports indicate that the CIA’s Counterterrorist Center failed to effectively act upon information provided by Thai intelligence regarding the movements of Khalid al-Mihdhar and Nawaf al-Hazmi, who traveled to the United States in early 2000.

Further lapses involved Zacarias Moussaoui, described as the ‘twentieth hijacker’. Despite his training at an Al-Qaeda camp in Afghanistan and his suspicious flight school activities in the United States, federal authorities and local agents in Minneapolis failed to connect his movements to a potential aircraft-based attack. Moussaoui’s contact with Ramzi bin al-Shibh, a key Al-Qaeda link, is noted as a missed opportunity for intelligence agencies to recognize the severity of the threat.

## Timeline

### 2026-09-10: Zacarias Moussaoui and the intelligence failures preceding 9/11

The case of Zacarias Moussaoui highlights a major intelligence failure by the FBI and CIA regarding Al-Qaeda's plans prior to the September 11 attacks.

2 sources. https://clstr.news/cluster/zacarias-moussaoui-and-the-intelligence-failures-preceding-911

### 2026-08-25: CIA and FBI intelligence failures contributed to 9/11 attacks

Intelligence failures and the confusion of key figures like Khalid al-Mihdhar and Khalid Sheikh Mohammed prevented the CIA and FBI from stopping the September 11 attacks.

6 sources. https://clstr.news/cluster/cia-and-fbi-intelligence-failures-contributed-to-911-attacks

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Cite as: US intelligence failures preceding 9/11 attacks. CLSTR, https://clstr.news/situations/us-intelligence-failures-preceding-911-attacks