President Andres Manuel Lopez Obrador has a strategy to cope with Central American caravans as well as President Donald Trump's push for a border wall and aversion to migrants.

That was the message from Mexico's first female ambassador to the United States, Martha Barcena Coqui, an experienced diplomat who was once a Fulbright scholar at the University of Delaware. She recently spoke at a global business conference held by the World Trade Center of Greater Philadelphia.

Known at home as AMLO, the leftist Mexican president (in office since December) has surprised U.S. observers who expected him to ignite fireworks with Trump. Instead, Mexican authorities have blocked groups of migrants at border towns. They also have permitted the Trump administration to send back several dozen migrants awaiting U.S. court decisions on their asylum applications.

But, Barcena told me, AMLO's stance is part of a broader Mexican approach on immigration.

Any debate on immigration, Barcena insists, "should be based on facts and realities." So here are some facts on the immigration dispute the Mexican government wants you to know.

1. When it comes to immigration, study the demographic profile of the United States, Mexico, and Central America as one region. "The United States has aged more slowly than Europe because of immigration, which has helped keep the economy buoyant," notes Barcena. However, the U.S. is now aging fast, while Mexico is still youthful. Central America is even more so. The youth bulge south of the border feeds migration north for jobs.

2. "Circular migration" — meaning some kind of legal guest-worker program — is crucial to meeting migration demand. From 1942-1964, the bracero program permitted Mexican laborers to enter the United States for seasonal work, and then return home. "When circular migration ended with the program, Mexicans continued to come because there were job opportunities," says Barcena. Many stayed illegally and later brought their families.

At present, H2A visas permit seasonal agricultural workers to enter and H2B visas (capped at 66,000) allow nonagricultural workers in when needed. But these programs are not always reliable, and need updating, especially now.

3. Central America will remain the main source of illegal immigrants and asylum seekers from south of the border unless root causes are addressed.

"People mostly migrate because they have no options," the ambassador says. "Sixty percent from Central America come from rural areas suffering huge drought." Others are fleeing gang violence. "If we can change the economy of the poorest areas of the region — from southern Mexico through Central America — and achieve sustained economic growth, then people will stay," argues Barcena. That will require joint U.S.-Mexican efforts. "Police measures to contain or deter can be useful in the short-term, but not the medium- or long-term."

4. AMLO is cooperating with Trump on migrants for pragmatic reasons. "We had three options," says Barcena. "We could have refused to accept returnees, meaning direct confrontation with the United States." But, she adds, "A fight doesn't help either country."

Alternatively, Mexico could have accepted the returnees and sent them back to their home countries, which is not in line with humanitarian principles.

Mexico chose the third option, taking back some asylum seekers and limiting the numbers who cross the border.

AMLO would like to see the number of legal ports of entry increased, and measures to speed up the legal flow, such as the use of huge security scanners. When I asked Barcena her opinion on "the wall," she replied, "Is a concrete wall helpful anywhere?"

When I pressed Barcena on why Mexican-U. S. relations have improved, she said: "I think there has been more respect from the White House. President Trump understands that President Lopez Obrador has 86 percent support in our country and won 53 percent of the vote."

Trudy Rubin is a columnist and editorial-board member for the Philadelphia Inquirer. Her email is trubin@phillynews.com.