Tier A - Overview
Date: September 11, 2001
Location: New York City; Arlington, VA; Shanksville, PA (USA)
Summary: September 11 attacks is remembered as a mass casualty incident with lasting lessons for prevention and response. The prevention lesson is to recognize escalation patterns early and act before capability meets opportunity.
Key prevention lens:
- Escalating grievance or fixation tied to a person, place, ideology, or perceived injustice.
- Leakage: statements of intent, threats, or ominous communications that merit documentation and follow-up.
- Preparation behaviors: access-seeking, planning, acquisition, testing, rehearsal, or sudden "energy burst".
- Track patterns over time and ensure fast information sharing across stakeholders.