The event considered to be the “spark” that started the War on Terrorism is 911
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Below are the choices:
</span><span>growing fear
uncontrolled rage
extreme happiness
deep bitterness</span><span>
I believe it would be the first one since there is anger or happiness in the context. I Would have to say fear because they don't understand something, and sometimes that can cause someone to be scared of the outcome. </span>