A friend expressed concern about how being political polar opposites has negatively affected her relationships in the past. Having any opinion is based on our perceptions, values and world view. When differences arise, regardless of the subject, we may take it personally when others disagree with us. After all, our values and world views are our truths. Disagreeing with our opinions can feel threatening and may undercut our confidence and belief in our own values. That could be scary and lead to arguments defending your position. Don't get me wrong, a good argument can be stimulating and create good solutions for people who fight fairly. However, people who get drawn into arguments about values-based issues, who want to impose their values on others, usually create a lose/lose outcome.
If you want to argue a values-based issue, be careful. Be a good speaker and educate the other about your opinion rather than try to persuade them to validate your opinion. Be a good listener and let them educate you. Who knows, one of you might actually change your opinion after you have listened respectfully and explored the other's value. In any case, whenever you are of an opposing opinion, enter the conversation from a learning stance. Keep an open mind, be a good listener and ask questions that will help them to educate you about their opposing point of view.