On Wednesday, Pope Francis is scheduled to celebrate Mass in Ciudad Juarez, Mexico, just south of the border with the United States. He will surely take that opportunity to urge support for the poor in Mexico and for those who have migrated north.

After all, that is what he did in September during his moving homily in New York's Madison Square Garden. Referring to the 11 million undocumented immigrants in the U.S., he asked his listeners to reach out to "all those people who don't appear to belong, or are second-class citizens ... because they have no right to be there."

But the absence of rights is a problem that is neither unique to the U.S. nor confined to immigrants who lack legal authorization to remain in the country in which they reside. Far larger and far more damaging is the difficulty that afflicts the 5 billion people who lack documented property rights. In Mexico alone, there are 10 million urban homes, 137 million hectares of land and 6 million businesses whose owners' rights are poorly protected.