When we talk about the decline of civility in America, it's important to explain what we mean by "civility".
Civility is showing mutual respect toward one another.
Civil discourse is the free and respectful exchange of different ideas. It entails questioning and disputing, but doing so in a way that respects and affirms all persons, even while critiquing their arguments.
It's important, when practicing civility and civil discourse, to share our viewpoints and to listen to others. It doesn't mean we have to agree, but it means we can disagree respectfully.