We can’t forget our past. We must be vigilant of history’s injustices and atrocities. No matter what stone we turn, there is a story to be found. Sometimes it lies in plain sight on the surface. Other times it is hidden deep underground. And, more often than not, the architects of a place’s history have used the stone as a foundation upon which they’ve built a museum of illusions, an image of what they would like the truth to be, and how they would choose to see themselves—but also a structure that shadows and obfuscates the truth, leaving millions in the dark about their own proud histories.

As a native Texan, I was raised on the refrain of remembrance. The Alamo. The Texas Rangers. How the West Was Won. Book-banning and curriculum-crafting forces will eagerly block any narrative that exposes the truths behind these myths and portrays their role in history as anything but glorious to the invader, the white Anglo man. But the truth is ugly. And we must remember it in order to avoid inflicting the same pain, horror, and inhumanity on innocent people again and again.

In 1918, a handful of boys in West Texas were accused of stealing some cows. The allegation—completely unfounded and unproven—mushroomed, for it was born not of truth but of prejudice. The white ranchers and settlers in the area were unabashed racists, back in those “glorious” times where it was considered perfectly fine and acceptable to hate others because of the color of their skin or the language they spoke or which version of Jesus they worshipped. By the time the Texas Rangers and U.S. Cavalry rode their horses into the border town of Porvenir, an entire conspiracy had been trumped up.

Fifteen Mexican boys and men were rounded up faster than any stray herd of elusive cattle. They were pushed to their knees, lashed to posts, beaten bloody, and summarily shot and killed to the horror of their mothers and daughters. For nearly two centuries their story simmered in the desert beneath the shimmering sands, yearning to be told. No mention appeared in the history books. No utterances were made in the classrooms, which in Texas are majority minority. No memorials were stood up in their name.

We must be vigilant of history’s injustices and atrocities.

We can’t forget our past. Today, along the same border, the government of the United States, and by extension its people, still treat other human beings like cattle. Because their skin is darker. Because they speak Spanish. Because they are poor. Because the same people who want to forget the past choose to believe that these “other” human beings bring America nothing but unwelcome change. They choose not to see the energy, the desire, the ambition, the willingness to work that these people bring. It is the same zeal that built the nation, oftentimes by the same kind of people—from abroad, many brought on slave ships.

The inhumanity at the border is not so different now than it was more than a hundred years ago. The Texas Rangers or Border Patrol do not routinely round up immigrants and murder them for all to see. But our immigration policies and the building of border walls and fences pushes immigrants to take ever more dangerous routes through the desert, resulting in hundreds of deaths every year. The detention centers and inaccessible approach to legal immigration are dehumanizing and discriminatory. As our country obstinately turns a blind eye to the suffering of immigrants and refugees, we cannot fathom the damage we are inflicting upon them, their children, and their families. A dream deferred. A future denied. Another atrocity swept under the rug in the name of the mighty.

We can’t forget our past. This is why I write about it. This is why in my new novel I imagine a version of our past where people of color help make and enforce the laws, dispense justice, and rewrite history. In that imagined past, those 15 Mexican boys and men from Porvenir survive. If we can acknowledge the failures of the past alongside its squandered potential, we can also remember and apply our insights and learnings to our present. It is a way we can envision becoming a better people, capable as a nation of emerging from the shadows of our own creation to fulfill the promise of liberty and justice for all.

Rudy Ruiz is the author of Valley of Shadows, released in September by Blackstone Publishing.