In public affairs & government, assorted interests argue for their views: best-case examples buttress their position, potential costs are minimized.
Use of military force (whether called "war" or "keeping the peace") is serious & potentially deadly. Decisionmaking processes should be methodical, not driven by hype & spin. Deployment decisions should include blowback analysis.
What potential worst-case scenarios can be linked to assorted options? What are the costs to doing nothing? Can we protect against counteroffensive, and at what cost?
Paths of action & inaction can each be costly - are we prepared to pay the expected price? Blowback analysis is essential. We should not be caught flatfooted, claiming surprise in the midst of failure.
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"I don't think anybody could have predicted..."
-- US National Security Advisor Condoleezza Rice (on enemies using hijacked airplanes as missiles); 16 May 2002
1994:
Bestselling novel "Debt of Honor" by Tom Clancy depicts a revenge-seeking pilot using a commercial Boeing 747 airliner to destroy the U.S. Capitol Building, killing the U.S. President and most of the nation's leadership.
1999 (two years before Sept. 11 2001 attacks):
"Sociology & Psychology of Terrorism" (link) -- U.S. Government 1999 report which discussed expected "spectacular" al-Qaida airplane strikes against U.S. targets.
March 2001
Nationally broadcast fictional Fox TV show "The Lone Gunmen" portrays the attempted crashing of a hijacked airliner into New York's World Trade Center.