Our beliefs shape us. They are tools for living. But everything is circumstantial. Sidedness is temporary. Your beliefs today may be incompatible with your system tomorrow.
Today's world requires you to deal with the subtleties that challenge your cognitive bias. The fact that you're Democrat, Republican, or Independent doesn't mean you have to see the world entirely in those views. You can hide away all day in your own cocoon but that does nothing to advance the discussion.
External forces influence your decisions: how you grow up, where you live today, your age, school/job, significant other, physical and mental health, and your family's well-being. Nothing is permanent. How you think, and act is a culmination of how things are right now.
It's not enough to side one way or the other 100%. But you can't sit out hang on the fence of sidedness either. Indecision still counts. Sometimes you have to play the cards you're dealt with even when you know they're better truths.