MEXICO CITY — The new president of Mexico, Andrés Manuel López Obrador, has built his entire political career on defending the poor.
Now, days before he takes office, President Trump is testing how firmly he will live up to that.
Thousands of migrants from Central America have massed along the border of Mexico and the United States — with thousands more on the way. American border patrol agents fired tear gas at them on Sunday to prevent hundreds from reaching the border.
Mr. Trump has vowed to keep the migrants on Mexican soil while they apply for asylum in the United States, a process that could squeeze them into squalid, overcrowded shelters for months, possibly even years. Mexican officials say the strain is already causing a humanitarian emergency, creating a political crisis for Mr. López Obrador even before he takes office.
Mexico’s foreign ministry said Monday it had presented a diplomatic note to the United States Embassy asking for an “exhaustive investigation” into the use of nonlethal weapons at the border on Sunday, where at least two dozen tear gas canisters released by American agents landed in Mexico. But the statement said Mexico would continue to cooperate with the United States on migration.
Later, at the White House, Mr. Trump defended the use of tear gas and said: “They’re not coming into the United States. They will not be coming into our country.” Although images showed families with children running from the gas, Mr. Trump said, “We don’t use it on children.”
After more than 15 years of campaigning as a leftist firebrand, Mr. López Obrador must swiftly decide: Will he stand up to Mr. Trump and defend the migrants’ pleas to be allowed into the United States, even if many of their asylum requests will ultimately be rejected? Or will he acquiesce to Mr. Trump’s demands and the economic imperative of good relations with the United States?
“The Mexican government is in a dead-end alley,” said Raúl Benítez Manaut, a professor of international relations at the National Autonomous University of Mexico. “López Obrador is facing a baptism of fire, and a dilemma of whether he should maintain his promises of humanitarian policies, or stop the masses of migrants trying to reach the U.S.”
Members of the new Mexican administration, which will take office on Saturday, view the situation with alarm. Top cabinet ministers had been preparing on Sunday to discuss what to do about the standoff with the United States — and their own country’s growing frustration with thousands of poor migrants streaming in from Central America — when their agenda was hijacked by the fracas at the border.
Three Places Where Migrants Tried to Cross the Border, Facing Tear Gas and Barbed Wire
Law enforcement used tear gas against migrants in at least two of the locations.
Suddenly, the incoming ministers found themselves watching videos of hundreds of migrants, including small children, rushing toward the border gates and getting tear-gassed by American border agents.
Mr. López Obrador, who has promised jobs and visas to migrants traveling north, now has to square his lofty campaign promises with some nettlesome international realities — as the whole world watches.
The question is, which version of Mr. López Obrador will be facing off against Mr. Trump?
Unpredictable. Temperamental. Beloved by his base and loathed by his detractors.
Mr. López Obrador, known by his initials AMLO, has been compared more than once to Mr. Trump.
And as is often the case with the American president, even his closest aides say they are not sure which Mr. López Obrador will emerge: the avuncular leader who preaches love and morality, the leftist firebrand who skewers opponents, the pragmatist aiming for a broader development deal for the region — or the impetuous politician who seems to make it up as he goes along.
For now, the new administration is being careful not to paint itself into a corner, noting that it has not taken office yet.
“We have little margin right now because we don’t have our own operation,” said Marcelo Ebrard, the incoming foreign minister. “Right now, we are just spectators.”
The disturbance at the border underscored the fragility of the situation. As more migrants from Central America gather — with as many as 10,000 expected to reach Tijuana in the coming weeks — the urgency to manage the chaos grows by the day.
Top officials in Mr. López Obrador’s new government fear that images of migrants trying to force their way into the United States will heighten the anti-immigrant sentiment that Mr. Trump has channeled so effectively in the United States. That could make it even harder to strike a resolution that involves compromise.
And while Mr. López Obrador has promised humane treatment for migrants passing through or staying in Mexico, it is unclear what his country will get for housing tens of thousands of migrants as they await asylum decisions from backlogged American courts.
The team around Mr. López Obrador is acutely aware that Mexico has long demanded humane treatment for its own migrants in the United States. Now, Mexico is facing scrutiny for how it treats migrants.
Local officials in Tijuana warned this weekend that they cannot shoulder the cost of the migrants, and they blamed the federal government for not providing money to open another shelter to handle the overcrowding.
For the time being, the city is cramming migrants into a sports center that already looks like an overwhelmed refugee camp, and many Mexicans are growing increasingly frustrated with the migrants’ presence, worried that they will take away jobs, resources and government attention from Mexican citizens. On Monday, Mexico increased federal police presence outside the sports complex.
“I’ve been feeling so desperate,” said Marta Alicia Martínez Padilla, 26, a migrant from Guatemala who added that her family had sold their tent to buy basic supplies like food and toilet paper. “I have no idea what to do.”
Since his election, Mr. López Obrador has set a course intended to keep a smooth relationship with Mr. Trump, who has made trade and migration the focal points of the complex relationship between the two countries.
Mr. López Obrador will take office on Saturday with an ambitious domestic agenda, intended to tackle Mexico’s entrenched inequality and spur development in the country’s impoverished south. The last thing he wanted was a conflict with Mr. Trump that might rattle Mexico’s markets.
That helps explain why, despite his long-held reservations over free trade, Mr. López Obrador signed off on a revised trade agreement that President Enrique Peña Nieto negotiated with the Trump administration, hoping to remove a central irritant in Mr. Trump’s approach to Mexico.
Mr. López Obrador also sought a way to placate Mr. Trump over migration — an issue that Mr. Trump has made a centerpiece of his appeal to supporters. In a letter to Mr. Trump a couple of weeks after his election, Mr. López Obrador laid out a plan to tackle migration at its roots — through development in Mexico’s southern region and at the border with the United States — as well as in Central America.
Mexico was prepared to dedicate money to the effort, Mr. López Obrador wrote, and if the United States partnered with Mexico and Central American nations, “we could gather a considerable quantity of resources to develop the region.”
His goal, he wrote, was that people could find jobs at home so that migration would be an option, not a necessity.
It was an ambitious proposal to a president who has focused on enforcement as the tool to limit migration into the United States. But then events in Central America took a turn that pushed the issue of migration to the forefront.
In October, migrants leaving Honduras formed a caravan to the United States, finding safety in numbers on the treacherous trip through Mexico, where they are prey for gangs.
Mr. López Obrador took a generous approach. There would be room for migrants in his development program in southern Mexico, he said, and his incoming interior minister, Olga Sánchez Cordero, discussed granting one million work visas to Central Americans.
But this weekend provided a case study of the problem brewing at the border.
Reports leaked that Mr. López Obrador’s government was in talks to potentially house all migrants applying for asylum in the United States within Mexico’s borders. Nearly as soon as the idea surfaced, cabinet officials insisted that no decision had been made.
“It is a complicated situation, but AMLO also has the opportunity to seize this crisis and this big moment,” said Claudia Masferrer, a migration expert at Colegio de México.
“In the short term, however, he has to deal with the migrants reaching the border and the tension in Tijuana,” she added, noting the rising anger at the migrants inside Mexico. “Even though AMLO has a high approval rate, this will create a strong opposition against him.”
First, Mr. López Obrador needs to “try to calm people down on Dec. 1,” when he takes office, she said, “because things are really heated up right now.”