Our exterior portrayal of calm and control is at the mercy of a neocortex that functions as a lighthouse, forever scanning the environment for safety. In the uncertain times we live in, from economic instability to the threat of terrorism and the uncertain fate of our planet, the signals we receive instigate our fears once too often.
Our cultural biases often make it difficult to see the prevailing side of an argument, especially when it's political in nature. Most of us inherit our politics from parents, peers, and social structures. When disagreement ensues, we tend to dig in our heels instead of trying to see the other person's point of view.