Tales from the Border Patrol

Francisco Cantu said he joined the Border Patrol at age 23 to get an on-the-ground education in international relations.

Now 32, he says he didn't expect his new memoir examining some of the agency's uglier aspects would spark protests by far-left groups denouncing him for the enforcement work and forcing him to cancel some talks promoting "The Line Becomes a River: Dispatches from the Border."

He said he agrees with much of the criticism from the left — even though it caught him off guard — and had expected most of the backlash to come from the right.

Cantu told his detractors on Twitter: "To be clear: during my years as a BP agent, I was complicit in perpetuating institutional violence and flawed, deadly policy. My book is about acknowledging that, it's about thinking through the ways we normalize violence and dehumanize migrants as individuals and as a society."

Cantu said he wrote the book to make sense of his time with the patrol.

"Writing the book was a way to come to terms with what I had participated in, a job that made me normalize a certain amount of violence," Cantu said. "I tried not to draw conclusions, but offer descriptions of what happened and a reflection of my state of mind."

Released last month by Riverhead Books, the memoir has collected positive reviews for its elegant prose about issues at the forefront of the nation's conversation on immigration and other border issues.

It braids together the history of the U.S.-Mexico boundary, Cantu's experiences with the migrants encountered by day and the dreams that haunted him at night.

Raised in Arizona's borderlands as the only child of a Mexican-American woman, Cantu thought several years in the agency would provide real-world experience for a diplomatic or legal career after graduation from American University. He joined the Border Patrol even though his mother warned of possible consequences.

"'You can't exist within a system for that long without being implicated,'" he recalled her saying.

Cantu worked for the agency from 2008-2012 trekking through the Arizona, New Mexico and Texas deserts. He encountered desperate migrants abandoned by traffickers in the desert, moved to bandage a woman's blistered feet and buy a man dinner at McDonald's.

He also spent countless, monotonous hours gathering intelligence at a listening post about sinister figures who lurked in the shadows and closely monitored the movements of Border Patrol agents.

When Cantu joined the force, he had "an idea about changing the system from the inside or bringing some good to it" but found the system "designed to break you down and rebuild you into an enforcement agent."

He wrote that agents' behaviour depended "on what kind of agent you are" when fleeing migrants leave supplies behind.

"It's true that we slash their bottles and drain their water into the dry earth, that we dump their backpacks and pile their food and clothes to be crushed and pissed on and stepped over, strewn across the desert and set ablaze," he wrote.

U.S. Immigration and Customs Enforcement officials haven't said anything about the book.

"It's just one person's opinion," Border Patrol spokesman Chris Sullivan said.