No amount of positive thinking will ever stop things outside of our control like natural disasters or human aggression. Nor will it stop us from making mistakes or just doing plain stupid things.
What the Law of Attraction can do is to improve the likely hood that we put ourselves in the environment and prepare ourselves to more likely notice opportunities that will improve the likelihood that the things we want show up in our life.
Positive thinking can help us to respond to the circumstances of our life in a way that benefits us, versus hurting us. When the results of our life are not what we want, we can take control and respond in a way that will benefit us, or we can react in a way that may be harmful to us.
Think of it this way, if you are waiting a long time for someone to show up for a meeting or date, how could you respond? You could get upset and express that to them. Does that help you? It may make you temporarily feel good to get mad at the person, though does it make for a productive meeting? Maybe there are some other ways to respond. You could decide to do something else and no wait for the person. You could decide that it is not important and be happy that they showed up. You could express concern that you thought they might have been hurt.
How would you feel if a doctor says your body is reacting to a medicine you just received? Now, how would you feel if the doctor says that your body is responding to the medicine?
Try taking control of your life and respond to situations instead of reacting.