The Rev. Daniel G. Groody, an associate professor of theology at Notre Dame University in Indiana, said the wall would lead to a loss of life as migrants are forced to find other ways to escape poverty across the border.

“What Trump fails to see is that state sovereignty is not an absolute privilege but a moral responsibility,” Groody told RNS.

“If more has been given to America, then even more is expected of us, and unless we attend to human insecurity outside our borders we will not have national security inside our borders.”

He said that even if the entire border is sealed off, “people are just going to come in boats. The wall solves nothing. It is just political bravado.”

Groody, who has worked extensively with migrants in southern California, was at the Vatican’s Pontifical Academy of Sciences in Rome taking part in an interreligious ethics project aimed at helping the poor.

“Significant spiritual issues are at stake,” Groody said. “To further close our doors not only deprives the stranger in need but also diminishes who we are as human beings.”

Groody said Pope Francis had made the plight of migrants a priority of his pontificate and Trump “understands neither the lessons of history, the challenges of immigration, nor the founding spirit of American democracy.”

Groody, who lived in Uruguay, Chile and Argentina under dictatorships, said after he was ordained as a priest he worked with immigrants in California on the border with Mexico.

“I was very inspired by the life of the people, the generosity of the people, but they were also suffering. They were not only poor, they were also dying in the deserts. Many were struggling for a dignified life.”