There is a phenomenon known as flashbulb memories where people report very detailed memories of...

There is a phenomenon known as flashbulb memories where people report very detailed memories of events that accompany high emotions (especially traumatic events). For example, people often have very detailed episodic memories of what happened on September 11th 2001 during the Twin Towers atrocity. Can you think of any evolutionary benefit for why people have detailed memories of traumatic events?