TUCSON — During the three and a half years I worked for the United States Border Patrol, from 2008 to 2012, America’s immigration enforcement never made less sense to me than when I tried to explain it to those most affected by it.

Once, patrolling the border fence, I was flagged down by a woman on the other side. She asked for information about her son. She didn’t know where or how long ago he had crossed, or whether he had been detained or become lost somewhere along the way. She didn’t even know whether he was still alive.

I struggle to remember what I told her. It’s possible I explained that crossing often entailed walking for days or weeks through the desert. It’s possible I suggested filing a missing persons report. It’s possible I gave her the number of a hotline that could match her son’s name and birth date to a person deep within the immigration detention system — a person regarded as a criminal by the United States government, another body filling a bed in a private detention center, a person who, to the woman trembling at the fence, represented the entire world.

After a month of outrage at the cruelty of President Trump’s “zero tolerance” policy, last week we saw a stream of confounding and divergent statements on immigration: The president suggested depriving undocumented migrants of due process; Attorney General Jeff Sessions insisted that every adult who crossed illegally would be prosecuted; and the commissioner of Customs and Border Protection announced that families would once again be released together to await trial. Meanwhile, thousands of separated children and their parents remain trapped in a web of shelters and detention facilities run by nonprofit groups and private prison, security and defense companies.