Bulletproof: The Making of an Invincible Mind is vital to developing a warrior mindset. It helps you learn how to become resilient in times of disaster so that you can do what you need to do in order to protect your family and survive.Keeping a resilient mind is probably the single most important factor in survival.
You can have all the fancy gear and still panic.
Training is useful, but I have seen trained people freeze or panic. However, history is full of examples of untrained and unprepared people survive all manner of hardship by having a strong mind, but it is also full of lottery winners, If you want to increase your odds, then you need to train.