Late last month, President Trump threatened to impose trade tariffs if Mexico didn’t help stop Central American migrants from reaching the U.S. border. In response, Mexican President Andrés Manuel López Obrador, known as AMLO, pledged to send 6,000 Mexican National Guard troops to his country’s southern border with Guatemala. The goal: prevent migrants from entering Mexico in the hope of later crossing into the United States.

But the Mexico-Guatemala border is over 500 miles long, geographically diverse and relatively easy to cross — at least at the geopolitical line. My field work at the Mexico-Guatemala border suggests that stationing more military there won’t deter migration. Rather, it is likely to make migrants easier targets for crime, encourage official corruption and perhaps prompt more migration from the borderlands.

Here are five things you need to know about why it is challenging to stem migration at Mexico’s southern border.

1. Here’s what Mexico is already doing

Since the 2000s, Mexico has been helping the United States deter Central American migration. Notably, in 2014, Mexico implemented the Southern Border Program, which increased mobile road checkpoints in Mexico’s southern state of Chiapas. From 2015 to 2018, Mexico deported more Central Americans than the United States did.

But expanding checkpoints along highway arteries has pushed migrants onto riskier, more remote and circuitous paths to avoid detection, or encouraged them to rely more on smugglers. Since 2014, abuses against migrants have skyrocketed; some reports contend that crimes against migrants in Mexico’s southern states have increased 200 percent.

The Washington Office on Latin America (WOLA), which promotes human rights in the region, conducted investigations between 2014 and 2016 that revealed just 49 sentences for over 5,824 reported crimes against migrants. That’s an impunity rate of 99 percent.

2. The Mexico-Guatemala border region has a different crisis

Both Mexicans and Guatemalans along the Mexico-Guatemala border are already facing economic and environmental stress, displacement, and restrictions on local trade.

The southern coastal region of the Mexico-Guatemala border has long depended on coffee sales. Coffee prices are dropping — while climate change is hurting both growing conditions and coffee quality. The Mexican peso’s value has also been falling, increasing hardship. As a result, Guatemalans and southern Mexicans are also trying to migrate north.

Since the Zapatista uprising in 1994, Mexico’s southern state of Chiapas, bordering Guatemala, has been filled with checkpoints and paramilitary surveillance of indigenous communities. In a state where Mexican indigenous identity is often conflated with being Guatemalan, many Chiapas peasants fear that more checkpoints will mean more abuses, constrained mobility and possibly detention.

What’s more, peasants in southern Mexico are increasingly losing their land and being treated as criminals for defending it. As of 2015, active mining concessions account for over 14 percent of Chiapas’s territory. Paramilitary groups, police, and private and mine security operatives have used threats, intimidation and violence to quell resistance on both sides of the Mexico-Guatemala border against dams and mines being constructed on indigenous lands. Many military bases ostensibly meant to control narco-trafficking and checkpoints to deter migrants are located near strategic resources, targeting migrants, locals and environmental activists alike. Just under half of the 99 mining concessions in Chiapas are along the coastal migration corridor from Tapachula to Arriaga, Chiapas — where WOLA documented 11 checkpoints. Checkpoints don’t just detain migrants or inspect for narcotics; they also prevent trade, surveil local inhabitants and invite corruption.

Border residents have always crossed back and forth for commerce, shopping and family connections. Having more highway and mobile checkpoints throughout southern border states interrupts livelihoods in a region where opportunities are scarce.

3. Involving the military in controlling migration could increase human rights abuses

Critics raise concerns over the military’s human rights record and its suitability for public security matters. Since 2006, Mexico has used the military to target drug trafficking, which hasn’t reduced violence or narcotics flows. Instead, drug-related homicides increased 15 percent between 2017 and 2018.

AMLO created the Mexican National Guard in December; Mexico’s Congress approved it in March. So far, the guard draws from former soldiers and police, who may not have any training in border and immigration enforcement.

The United Nations has agreed to train the Mexican National Guard on human rights, but the rush to mobilize raises concerns about adequate training and accountability to respect migrant rights, report abuses, and guarantee access to refugee protections as enshrined under international and Mexican law.

4. Militarization may increase crimes against migrants and aggravate corruption

Authorities are often complicit in crimes against migrants, whether as perpetrators or by failing to report and investigate those crimes. Of 118 migrant complaints about abuses submitted to a shelter on the Guatemalan side of the Mexico-Guatemala border between 2010 and 2015, roughly a third of the allegations were against state authorities, mostly by migration authorities and federal and municipal police. Most crimes consisted of abuse of authority, extortion, or bribery under threat of deportation, although some accused authorities of complicity in illegal detention, robbery and assault.

5. Mexican National Guard proposals misunderstand the region

Putting more military at the border is unlikely to seal it. This approach fails to grasp the environmental and political landscape.

When I conducted my field work in 2007, I told residents about a proposal to install a formal checkpoint at a nearby unmonitored crossing. If the border was closed here, they reasoned that they would cross over there, pointing to the vast hillsides.

Border residents also recall that in the 1980s and early 1990s, Mexican police and Guatemalan soldiers were scattered throughout the border terrain. Rather than provide security, customs and immigration officers made deals with residents, migrants and smugglers. Officers feared that fully applying the law would result in local uprisings or even violence — as when a community burned down a small migration checkpoint in the 1990s.

Making it harder for border residents to earn their livelihoods by traveling back and forth is the real security concern for residents. It could actually propel more to migrate to the United States.

Read all TMC’s immigration analysis here.

Rebecca Galemba (@RebeccaGalemba) is an assistant professor at the Josef Korbel School of International Studies at the University of Denver, and author of “Contraband Corridor: Making a Living at the Mexico-Guatemala Border” (Stanford University Press, 2017).