(Photo by Beowulf Sheehan)

Francisco Cantu is the author of "The Line Becomes a River: Dispatches from the Border."

As part of efforts to increase border security, the Trump administration has proposed hiring 5,000 additional Border Patrol agents.

But there have been concerns that some agents destroying water left in the desert by humanitarian aid groups and that migrants are seen as threats to American security rather than as people looking for economic opportunity.

Former Border Patrol agent Francisco Cantu writes about those issues and others in his new book, "The Line Becomes a River: Dispatches from the Border."