and fear takes time to develop
Well, I think I will take issue with this statement. From practical experience, the acute attention physiological response (Fear response)takes about 1 heartbeat. You know when it hits you because your heart violently contracts (like it did the time another formation interleaved the formation I was in at 90 degrees to our heading).
Can you quote your source for this physiological observation of yours?
To reach the kind of fear you are suggesting takes input, observation. the lizard brain demands data, it cannot think on its own.