The normalcy bias, or normality bias, refers to a mental state people enter when facing a disaster.

Is it a crime to be an 'alarmist' when there is actually cause for alarm? How many will we persecute for crying fire before we realize the theatre is actually ablaze?

 It causes people to underestimate both the possibility of a disaster occurring and its possible effects. This often results in situations where people fail to adequately prepare for a disaster, and on a larger scale, the failure of governments to include the populace in its disaster preparations. The assumption that is made in the case of the normalcy bias is that since a disaster never has occurred then it never will occur. It also results in the inability of people to cope with a disaster once it occurs. People with a normalcy bias have difficulties reacting to something they have not experienced before. People also tend to interpret warnings in the most optimistic way possible, seizing on any ambiguities to infer a less serious situation.

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