Eclipses have come at dark times in US history, but we can find the light

"Maybe you have to know the darkness before you can appreciate the light."

As Madeleine L'Engle wrote, "Maybe you have to know the darkness before you can appreciate the light." But even her books, filled with beautiful words that touched many people, were banned for many years.

Watching the tragic events of Charlottesville, Virginia, this past week and saddened by a president who abdicated any moral authority in the midst of it, I realize our country, while having the best of ideals and people, often experiences an eclipse of that light by dark moments in our history.

From my experience as an Irish Catholic from Detroit, I have seen evidence of these injustices. My ancestors felt discrimination because of their Irish heritage, the religion they practiced, and as a young child, I witnessed the devastation of the Detroit riots.

We and our country do not have to be defined by our dark moments, but we must learn from them and continue on a path, as the Constitution says, to "a more perfect union."

Though we should expect light to break through, even as good people, we will be part of some darkness. We each stumble and fall, and we each have our own biases. Often we choose fear over love and slip into division instead of unity. But we shall — and we must — overcome.

We must also understand that our ideals and democracy are gifts; they are not a given. It takes good people reminding others, through both words and deeds, that we must move forward to reach the promised land of love and justice.

The total eclipse will fade quickly next week, and we will enjoy the light our sun offers. We will also get through this moment and emerge with our wounds bandaged and the will to reform and heal our brokenness. I have faith that we will show a strong force of love to push out the hate.

As Desmond Tutu said, "Hope is being able to see that there is light in all the darkness."

Matthew Dowd is an ABC News analyst and special correspondent. Opinions expressed in this column do not necessarily reflect the views of ABC News.