Large groups of Central American migrants are walking north through Mexico, defying President Trump and facing little resistance from authorities. Although Trump has described the groups as “invaders,” those walking are unarmed, and many are women and children who say their goal is to seek asylum in the United States. We will be tracking the caravans' advance through Mexico and U.S. preparations for their arrival at the border. What you need to know:

  • Two caravans, each with more than 3,000 travelers, are trailed by at least two additional groups of several hundred migrants
  • Trump has said up to 15,000 U.S. troops could be sent to the Mexico border, far more than the 5,200 additional personnel announced by the Pentagon
  • The Trump administration also is considering a plan to deny asylum to migrants at the border

How close is the caravan to the U.S. border, and where will it arrive, Texas or California?

Reporter Maya Averbuch has been traveling with the lead caravan group. She sent this dispatch from the soccer stadium that authorities in Mexico City have set up as a sprawling camp for the migrants:

On Wednesday, around 5,000 caravan migrants remained stationed in a sports center in Mexico City. The majority had boarded trucks and trailers in the state of Veracruz to make it to the capital. The first part of the group Sunday, and others have trickled in since then, nursing sore feet, chest colds and fatigue.

Over the coming days, they will have to decide where to go. The soccer stadium has afforded them enough space to sprawl out on bleachers, hang their clothes to dry outside huge tents and make phone calls back to their families in Central America.

But after several days of rest, the group is growing impatient. In the evening, they will gather for a vote to determine which route to take. The most likely destination would be Tijuana, because it promises the safest path to the U.S.-Mexico border. But it’s also the longest.

“We don’t know what route we’re going to take,” said Carlos Alonzo Escobar, 29, a Salvadoran member of Pueblo Sin Fronteras, an activist group that has been guiding and assisting the caravan.

Migrants who want a shorter trip could travel along Mexico’s Gulf Coast, toward the Rio Grande Valley of south Texas, a journey of about 600 miles.

They could opt for a middle route that would take them toward El Paso. But these options could be more dangerous, taking migrants through areas with some of the worst reputations for attacks by criminal groups.

The Tijuana-San Diego route is considered safer, but it’s at least twice as far as south Texas.

“I want the longer, safer route for my family,” said Lester Oseguera, 30, from Colón, Honduras. “We don’t want to have people be killed or kidnapped just because we’re in a hurry.”

Hasn’t illegal immigration declined by a lot? Why all the fuss over a few thousand people in caravans?

In 2000, the year before the Sept. 11 terrorist attacks, the U.S. Border Patrol made 1.6 million arrests along the Mexico border, a record. The agency had fewer than half as many agents in the field then, and in several areas along the border those agents would spend an entire shift rounding up and deporting large numbers of migrants who were overwhelmingly from Mexico and male.

The Arizona deserts were the border’s busiest place, and agents in the Tucson sector made more than 50,000 arrests every month that year. As one agent who worked during that era told The Post, “it was like a riot every night.”

The prevailing currents at the border have completely changed since then. Last year, the Border Patrol made 303,916 apprehensions, the lowest level since 1971, and while that figure jumped to 396,579 during the fiscal year ending Sept. 30, border arrests remain far closer to historic lows. (See table below.)

Annual arrests along the U.S.-Mexico border (Chartable/The Washington Post)

So what’s the big deal with a few thousand people in a caravan? Why is the Trump administration claiming there is a “crisis” at the border?

The big change — and the thing that is so galling to Border Patrol agents and the Trump administration more broadly — is that the government now has an extremely difficult time detaining and deporting the migrants taken into custody. They’re Central American families and kids seeking asylum, not Mexican laborers who are, by comparison, easy to deport.

Basically, the government’s enforcement model is being short-circuited by Central American migrants who, unlike Mexican nationals, cannot be bused to the border and deported. This new wave of migrants consists increasingly of parents with children who request humanitarian protection and express a fear of return, steps that slow or stop their deportation.

This is the administrative path to a shot at a better life in America.

Most migrants who arrive with children turn themselves in to Border Patrol agents and go through a screening to see if their fears are “credible.” They typically spend a few days in custody, and then they are released pending a court appearance for their asylum claims, because courts have limited the government’s ability to hold kids in immigration jails for longer than 20 days.

This is the model the Trump administration abhors as “catch and release” even as the practice has become its de facto enforcement policy at the border.

One result is that more than half of all those taken into custody along the Mexico border today are family groups or underage minors traveling alone. And the number of “family units” (consisting of at least one parent and child) is at a record high (see below).

So while the migrant caravans moving their way north — perhaps 5,000 to 10,000 travelers in total — amount to only 10 to 20 percent of the 50,000 or so people arrested along the border each month, they symbolize what has become, for the Trump administration, a real crisis for its enforcement model.

This is why we’re also likely to see new administrative attempts to tighten the asylum process, perhaps in the coming days, while the caravans remain more than 600 miles from the U.S. border.

Estimates of the caravans’ size keep changing. How many migrants will make it all the way to the U.S. border?

Let’s start off by dispensing with some facts whose accuracy has expired — namely that a caravan of more than 7,000 migrants is walking to the U.S. border. That was true two weeks ago, but since then the main caravan has been whittled by attrition, while smaller, subsequent caravan groups have formed behind it, picking up some travelers and leaving others behind.

It’s also not the case that migrants are walking the whole way. As The Post’s Maria Sacchetti reports from the state of Veracruz, where she’s been traveling with part of the main caravan, footsore travelers have been hitching rides on trucks and trailers, some dangling from vehicles in precarious contortions.

This means some migrants will stray from the main groups, if they’re able to find transportation. Some of caravan groups began arriving in Mexico City on Monday, settling into a makeshift camp at a soccer stadium.

SANTIAGO NILTEPEC, MEXICO - OCTOBER 30: Migrants traveling in a caravan toward the U.S. border, including Miguel de Jesus, age 4, ride on a truck last week along a highway in Santiago Niltepec, Mexico. (Photo by Carolyn Van Houten/The Washington Post)

Either way, the journey is grinding down and breaking up the caravans, and they’re still at least 700 miles from the U.S. border.

Nearly 3,000 migrants have accepted offers to apply for asylum in Mexico, authorities there say, and another 500 have given up, asking authorities for help returning home to Central America.

That appears to leave at least 5,000 people, clustered in several groups, who remain on course. How many are likely to complete the journey?

Preliminary assessments of the first caravan by U.S. military planners anticipated only about 20 percent of the travelers would make it to the border. That would be as few as 1,000 people, if accurate. Awaiting them are 7,000 active-duty U.S. troops, 2,000 National Guard personnel and the thousands of Border Patrol agents and customs officers who will have the lead enforcement role.

Perhaps 1,000 is a lowball estimate, and two or three times that many will reach the border. If they were to reconvene as a single group, they could present U.S. authorities with a crowd-control challenge at ports of entry or along the banks of the Rio Grande.

But in terms of an overall impact on border enforcement, this would not amount to a major surge. Last month, U.S. authorities took more than 50,000 into custody along the Mexico border. So even if all 5,000 migrants who remain in the caravans were to complete the journey, they would amount to 10 percent of those intercepted each month.

If anything, the caravan’s evolution from one big group into several smaller ones was probably inevitable, because fragmentation brings several practical advantages, as long as the migrants remain in groups large enough to offer safety from potential attacks. And large enough to make Mexican authorities think twice about trying to corral and arrest them.

A single, massive procession of several thousand people was useful for getting across the Guatemala-Mexico border, but not for the vagaries of the long journey through Mexico. When caravan groups are too large, they overwhelm the ability of towns and charities to help them. They move too slow. And they make it easier for the Mexican government to keep them in a slow-moving herd, instead of more-nimble hitchhikers.

All of this increases the likelihood that the “caravan” will not reach the border as a single cluster, but as a succession of smaller groups, and in numbers that might not look like the kind of security threat that would warrant an extraordinary deployment of American troops.

JUCHITAN, MEXICO - NOVEMBER 1: Roxana Orellana, 21, who is nearly five month pregnant, and Kevin Flores, 26, both from Honduras, stand for a portrait before continuing their journey north towards the United States border with thousands of other migrants in Juchitan, Mexico on November 1, 2018. (Photo by Carolyn Van Houten/The Washington Post)

Trump is threatening to jail caravan migrants in “massive tent cities” and warned that U.S. troops could fire on anyone throwing rocks. Did that scare anyone?

The Washington Post’s Michael E. Miller spoke to caravan members late Thursday, as news of Trump’s speech reached their encampment in Matias Romero Avendano, Mexico. Here’s his dispatch:

The migrants were resting in a soggy sports field on the edge of town, a few miles from where Mexican families celebrated the Day of the Dead in the town cemetery.

“They won’t shoot because we’re not criminals,” Erik Miranda, 39, said of Trump’s threat that U.S. troops would open fire if attacked with rocks. “I lived there for 15 years. I know the United States is a country of laws.”

Miranda said he had been deported from America twice despite asking for asylum after being shot three times by the 18th Street gang in his native Honduras. “If the caravan reaches the border and enters, these people will have their day in court in front of a judge,” he said.

Miranda said he would not try to enter the United States again but instead was hoping to reach Mexico City, where he planned to request asylum.

“How horrible,” Daniela Carbajal, 27, said when told of Trump’s threat. “I’m not justifying throwing rocks but remember: We have children among us.”

As she spoke, her 9-year-old son, Oscar, watched a video advising migrants of their rights, his head poking out of an orange tent Carbajal and her husband had just bought for 150 pesos. Inside, her 3-year-old daughter, Karla, was sound asleep. 

Could Trump’s military deployment turn lethal, and under what circumstances are U.S. troops authorized to use force?

Trump’s threats carry a not-so-veiled suggestion of military force. Such a scenario has long been promoted by extremists who believe lethal violence is an acceptable response to illegal border crossings. And the president himself repeatedly depicts the migrants in warlike terms, characterizing their journey as an “invasion” consisting of “tough fighters” who “fought back hard and viciously against Mexico,” according to his tweets.

All of this raises a disturbing question: Under what circumstances would U.S. troops open fire?

The Pentagon has been deeply wary of such a scenario. The 2,000 or so National Guard troops who have been assigned to the border since April are not supposed to make arrests or carry weapons, as a general rule. And active-duty forces are limited by the Posse Comitatus Act, a 19th-century law curbing troops' ability to carry out law enforcement duties on U.S. soil.

At the border, the use of active-duty forces has also been haunted by a 1997 fatal shooting of a teenage shepherd — an American citizen — who U.S. Marines thought was a drug runner.

The new deployment, an operation the Pentagon is calling “Faithful Patriot,” appears less troubled by such a possibility. The troops — at least 5,200 but maybe more — will include armed units, and their rules of engagement appear to be significantly less restrictive.

The latest caravan groups have acted more unruly and confrontational toward authorities in their path. One contingent broke through a gate at the Guatemala-Mexico border last week, and on Sunday, members of a second caravan pelted Mexican police with bottles and stones. A man from Honduras died in the clashes, apparently struck in the head by a rubber bullet.

If a large part of the caravan reaches the U.S. border — by no means a sure thing — U.S. authorities fear a large crowd could attempt to overrun U.S. barriers and enter the country by force. But that alone would not be sufficient to justify a lethal response from troops.

As The Post’s Paul Sonne, Dan Lamothe and Missy Ryan report, citing Pentagon planning documents, “troops will deploy with a mixture of lethal and nonlethal weapons and are authorized to use deadly force in defense of ‘all persons, foreign or domestic, who are faced with imminent threat of death or serious bodily harm, and where lesser means have failed or cannot be reasonably employed.’”

That said, the soldiers are supposed to operate in an auxiliary role. The Border Patrol and U.S. customs officers will be the ones making arrests and potentially confronting caravan members if they attempt to enter the country unlawfully.

Among the activities the soldiers are supposed to carry out: constructing barriers and fencing, providing helicopters and fixed-wing aircraft to transport Border Patrol agents and providing medical care.

(Tim Meko/ The Washington Post)

Trump’s show of force at the border is an election ploy, right?

The president’s political calculation here is impossible to ignore. He seems determined to make the caravan appear as dangerous and threatening as possible — and to cast himself as a kind of border sheriff. He has claimed, without evidence, that “Middle Easterners” have infiltrated the group. Administration officials insist that the caravan is full of gang members and criminals, again without proof, because, well, odds are that bad people are mixed in.

That said, the migrant caravan, and another one with about 3,000 people that crossed into Mexico on Monday, have stirred up some bona fide fretting at the Department of Homeland Security. The scenes from the Guatemala-Mexico border last week, in which thousands of people broke down a border gate and forced their way into Mexico, are nightmare scenarios for DHS.

So who is really in the caravan?

The main caravan, which DHS says numbers about 3,500 people, and a second caravan that entered Mexico on Monday with about 3,000, includes a lot of destitute families seeking a better life in the United States. Others are deportees trying to return to the lives they lost after they were arrested — some for committing crimes — and sent back to Central America, as The Post’s Joshua Partlow describes in this vivid account of a single day walking with the group along a 28-mile leg of the journey.

He met one traveler, Jose Vega, 38, a Honduran deportee who once worked construction in New Orleans and told him that the United States is “a promised land, a sanctuary."

“To reach any sanctuary, you have to take risks,” Vega told him. “My hope is someday to build a house, for my family to live in peace, to go from sandals to shoes. Not to be rich, but to be in peace."

The White House wants a travel ban for the Mexico border. How would that work?

On Friday night, The Post and other media outlets reported on a plan under consideration at the White House that would use the president’s executive powers to deny entry to Central Americans, and restrict or suspend their ability to seek asylum in the United States. Details of the proposal remain sketchy, but draft versions would rely on the same legal provisions the administration used during the travel ban in early 2017.

By citing national security concerns, Trump could refuse entry to certain Central American nationals or another subgroup, including members of the caravan. Trump is also weighing a measure that would deny asylum seekers the ability to seek humanitarian relief once they reach U.S. soil, according to administration officials and people familiar with the proposals.

Both moves would land the administration in federal court “in about five minutes,” one former Homeland Security official said, and it’s not hard to imagine lower court judges slapping an injunction on a White House “border ban” in about as much time.

Trump already won legal victories on this front. Wouldn’t a ban on Central Americans and asylum denials stop the caravan?

Not likely. The administration’s biggest challenge at the border is not that too many Central American migrants are being allowed in or that they are easily winning asylum. Rather, those who cross illegally — between ports of entry — must be taken into custody. U.S. detention capacity is nearly maxed, and U.S. courts limit the government’s ability to keep children in immigration jails beyond 20 days.

It is not as though huge numbers of Central Americans are winning asylum, either. The latest statistics show that fewer than 10 percent of Central American applicants are granted asylum by an immigration judge, but it is the act of coming over, applying for it and waiting for the legal process to play out that has become such an alluring way for impoverished migrants to live and work in the United States, if only for a few years.

That brings us the big flaw with the Trump administration’s proposal for a “ban.”

It is one thing to do it at a foreign airport thousands of miles away. It is another to try it on the banks of the Rio Grande. If members of the caravan reach the U.S. border and are denied the ability to approach ports of entry — the official crossings — they probably will go to the river or into the desert where they can walk across.

Then they will be on U.S. soil. The Border Patrol will have to take them into custody. Unless Mexico agrees to take them back, the migrants would have to be held in detention until they can be deported. But if the migrants are accompanied by children, the government has virtually nowhere to put them.

Children travel on a cattle truck as a caravan of Central American migrants slowly makes its way between Pijijiapan and Arriaga, Mexico, on Friday. (Rodrigo Abd/AP)

Didn’t Trump already deploy the National Guard to the border?

Yes. Trump sent U.S. troops to the border this spring, when another caravan piqued his anger and fueled similarly bombastic tweets. At the time, Defense Secretary Jim Mattis authorized the deployment of up to 4,000 National Guard troops but restricted their activities — so they don’t make arrests, carry weapons or interact with migrants.

About 1,600 Guard troops remain along the border, mostly in Texas.

U.S. Border Patrol officials insist that the Guard troops are a big help, saying they free up agents to concentrate on drug interdiction and enforcement duties “along the front line."

The Guard forces fly drones, monitor sensors and operate other surveillance equipment. They perform data entry tasks at Border Patrol stations. Others have been assigned more mundane jobs such as clearing vegetation and tending to horse stables.

When will the caravan reach the United States?

The caravan is still more than 1,000 miles away from U.S. territory, and the map below shows there is a lot of Mexico left to traverse. If the group manages to advance 15 miles per day, it would take more than two months for it to arrive at the Rio Grande. And that’s a lot of distance for families with children to cover.

That timeline changes significantly if caravan members manage to board buses, trucks or freight trains, in which case they could reach the U.S. border in less than a week. But that is a major if, absent a significant fundraising effort to provide mass motorized transport.

Isn’t that what happened with the last caravan — the one that angered Trump earlier this year?

Yes. That caravan, organized by a migration activist group, Pueblo Sin Fronteras, grew to about 1,500 people at one point. About 400 ended up crossing into the United States to seek asylum.

The big difference? That caravan was organized. It had leaders, legal advisers and a support network in the United States and Mexico. Most important, it had chartered buses.

Rather than attempting to cross in the Rio Grande Valley — the closest place, geographically, to Central America — that caravan traveled all the way to Tijuana. That made sense, because it had a large contingent of supporters on the California side. The caravan’s legal advisers steered members to the U.S. ports of entry, where it is legal to enter the United States to request asylum.

Will this caravan follow the same course?

At this point, and with no one leading or directing the movement, there’s no way to tell. It’s possible that the group will break up along the way and fan out to different areas along the border, where some will approach ports of entry to seek asylum and others may attempt to sneak across and evade capture.

Trump seems determined to avoid a replay of the chaotic scenes last week at the Guatemala-Mexico border bridge, where crowds forced their way through barriers and thousands surged into Mexico with no screening or checks. If thousands of migrants were to mass like that opposite McAllen, Tex., or another U.S. border city, it is not hard to imagine a volatile confrontation.

How did this caravan get so big?

The United Nations estimated that more than 7,000 people have joined the caravan, although the size of the group appears to be fluid. Most of those traveling north are from Honduras, where the caravan originated. There has been no evidence of any “Middle Easterners” in the group’s ranks, as Trump has alleged.

Predictions about how many of its members will eventually reach the U.S. border are difficult to make. It is probable that the caravan’s size will remain elastic as some drop out or turn back, and others join in.

It’s important to remember that more than 50,000 people were taken into custody last month along the U.S.-Mexico border, so even if 5,000 caravan members go all the way, they would represent a fraction of current flows. As one Homeland Security official put it: “We get a caravan every day.”

Many of the migrants have told reporters that their decision to leave was made in a flash. They had been waiting for an opportunity to come along but could not afford to attempt the journey any other way. The cost of hiring a “coyote” smuggling guide to go from Central America to the United States can exceed $10,000. But grabbing a backpack and hitting the road with a mass movement? That’s free.

And on a route beset by kidnapping gangs, extortionists and other predatory criminals, joining a caravan offers a degree of protection. There’s safety in numbers, and the processions attract many police officers.

A man pushes his daughters as they make their way to Mapastepec, Mexico, on Oct. 24. (Rodrigo Abd/AP)

Why doesn’t the Mexican government stop the caravan?

The Trump administration is leaning hard on Mexico to make a stand and block the group’s advance. There are several reasons that has not happened — and remains unlikely to happen anytime soon.

A big one: The six-year term of President Enrique Peña Nieto will end Dec. 1. He is one of the most unpopular presidents in recent Mexican history. He has little incentive to use escalating force on impoverished Central Americans to appease Trump. That would be humiliating for him.

Mexico already is taking steps it has not in the past, soliciting help from the United Nations to screen and process asylum seekers, and the government says that more than 1,000 caravan members have done so. Mexican federal police officers also held off the caravan at the border with Guatemala last week, although many of those migrants simply waded through the river to continue their journey.

It is important to note that there is little stigma in Mexico to joining a caravan like this in hopes of reaching the United States. Poor Central American migrants are treated more like pilgrims than criminals. When they arrive in Mexican towns, people offer food, clothing and other donations as a way to support them and to encourage them to move on.

In a heavily Catholic country, and at a time when Pope Francis has urged sympathy and support for migrants worldwide, many Mexicans think they have a moral duty to help the caravan. An attempt by their government to repress the caravan by force would clash with that sentiment and court political disaster.

Read more:

The border is tougher to cross than ever. But there’s still one way into America.

Seeking asylum: One family journeys with the caravan from Honduras to the Bronx