The united states' response to the september 11 terrorist attacks is an example of structural defense policy. crisis policy. strategic policy. partisan defense policy. preemption.

I believe the answer is: crisis policy

Crisis policy is The type of policy that created in order to take care of negative situations which couldn't be handled using existing protocols.
After the 9/11 terrorist attack, the united states government created a more advanced security measure in airports that never exist prior to the attack.

Everyone’s hair grows differently.

Hope this will !