It’s hard to talk about touring the slave castles along Ghana’s coast without resorting to clichés. The unspeakable horror of these places is palpable as you walk through the dark dungeons. It’s a sobering and humbling experience for a white American whose privilege was built on the backs of these men and women.

In 2009, Barack and Michelle Obama toured Cape Coast Castle with their family after Michelle traced her family’s history as slaves in America to this very place. I’m often cynical about the way humans treat each other, but this moment feels to me like a milestone in human progress. A family that was once enslaved by our country is now living in the White House and touring the world as our global ambassadors. The times they are a changin’.

I’m not so naive to think that slavery is a thing of the past. I know it has only changed its shape and become less visible, but a moment in history like this gives me hope that Martin Luther King, Jr. was right when he said “The arc of the moral universe is long, but it bends toward justice.”