The problem with an impenetrable fortress is that while no one can get in, no one can get out either. Self protection is a natural defense, however it’s not always the best one. Sometimes you are safer paddling further from shore, than staying close to land where the surf and rocks are more dangerous. Sometimes you have to lower the gates and let the enemy in. Sometimes the payoff justifies the risk. Of course, sometimes you just get screwed. In the end, it’s your choice.