It's partly in the very definition of the word. > panic: sudden uncontrollable fear or anxiety, often causing wildly unthinking behavior. When fear runs wild

It's partly in the very definition of the word. > panic: sudden uncontrollable fear or anxiety, often causing wildly unthinking behavior. When fear runs wild and uncontrolled, it can paralyze us into inaction, or worse yet, motivate us unthinkingly towards action that may end more lives than even inaction would. Or to put it another way - panic is a great way to waste a bunch of perfectly good fear. Fear should be properly harnessed, controlled, and guided through proper thinking and wisdom - then we can maximize our chances of it motivating us to take those extreme, life saving actions you alude to. Stress - as caused by fear - can shorten your lifespan and reduce it's quality as well. When possible, one should guide ones fears towards reasonable risks you can do something about - where the costs might be worth it - and away from the irrational or unactionable - where they are not.