My friend Erroll Southers, who has spent his career in law enforcement and served in my administration’s homeland-security department, wrote today: “I still get nervous when I receive the unexpected phone call at an odd hour, hoping my son, brother or relative has not become the next hashtag.”

Think about that. Erroll Southers is a professor at USC, a former FBI agent, an upstanding man in every sense of the word, and because of the color of his skin, when his phone rings in the middle of the night, his first thought is that his son or brother might be the reason for the next march.

I can’t even fathom that experience. If my kids FaceTime me late at night, it brings me joy, or maybe if they’ve been at a party, a laugh. It is completely unjust that for much of our population, those family calls bring anxiety.

It’s wrong, it’s unfair—and that’s why people are marching today.