In the almost three years since President Donald Trump took office, the US asylum system has almost become unrecognizable.

The administration has built up, layer by layer, a series of impediments in Central America, at the border, in detention centers, and in the immigration courts that have made obtaining asylum nearly impossible.

The changes have been made quietly and have never been able to inspire the kind of public outrage sparked by Trump’s travel ban in January 2017 — when thousands of people flooded airports to stand up for people barred from entering the US — or the outrage toward the “zero tolerance” policy that led to family separation in spring 2018.

Trump ultimately backed down on separating families in immigration detention. But the policy was only one piece of a much broader, concerted effort to stymie asylum seekers orchestrated by White House senior adviser Stephen Miller — who, despite retreating from public view while Trump has been in office, has been instrumental in implementing policies that immigration restrictionists have long sought.

“My mantra has persistently been presenting aliens with multiple unsolvable dilemmas to impact their calculus for choosing to make the arduous journey to begin with,” he told US Customs and Border Protection officials in a memo first reported by NBC.

Migrants have the right to pursue asylum in the US if they have “credible fear” of persecution in their home countries on account of their race, religion, nationality, political opinions, or membership in a “particular social group,” such as a tribe or ethnic group. Once they are granted asylum, they can obtain social services through refugee resettlement agencies and apply for a green card one year later.

Historically, most asylum seekers apprehended while trying to cross the southern border would have been placed into deportation proceedings, but released into the US while awaiting a decision on their immigration cases. Under the Trump administration, that changed dramatically.

“What we have seen, unlike any other administration, is a series of measures that are interlocking,” Muzaffar Chishti, director of the Migration Policy Institute’s office at New York University School of Law, said. “When you look at the combination of these interlocking mechanisms, we have essentially revised — some people would say gutted — our modern asylum system as we know it.”

Trump promised on the campaign trail to build a wall on the southern border and make Mexico pay for it. While that plan hasn’t exactly come to fruition, Trump’s policies are, with the cooperation of Central American countries, targeting asylum seekers well before they reach the southern border, and achieving the same effect.

“Mexico together with other Central American countries have built a wall for the president,” Chishti said. “It’s just not on the border.”

Here are seven ways the Trump administration has made it all but impossible to seek asylum in the US.

1) The Trump administration wants to send migrants back to Guatemala, Honduras, and El Salvador

Over 978,000 migrants have arrived at the southern border over the past year. They are mostly coming from the Northern Triangle countries of Guatemala, Honduras, and El Salvador, where rampant crime, violence, and corruption is driving hundreds of thousands to flee. In those countries, migrants are commonly robbed, kidnapped for ransom, raped, tortured, and killed.

El Salvador has the highest homicide rate in the world. Honduras is fifth, Guatemala is 16th, and Mexico is 19th, according to the United Nations Office on Drugs and Crime. Each country has rampant government corruption and high rates of violence against women and LGBTQ individuals, and remain hotspots for international criminal gang activity. The US State Department has issued travel warnings for US citizens in all four countries.

The administration has nevertheless sought to send migrants back to those countries.

It issued a sweeping rule in July that prevents migrants from being granted asylum if they passed through any country other than their own before arriving in the US — meaning asylum seekers showing up at the southern border who are from any country but Mexico are effectively ineligible for asylum (although some migrants would still be eligible for other protections that would allow them to stay in the US).

The Supreme Court allowed that rule to temporarily go into effect across the border in September while a lawsuit over the rule makes its way through the courts.

There are limited exceptions to the rule: Those who apply for asylum in another country but are rejected may bring their claims in the US. Victims of human trafficking and migrants who traveled through countries that are not parties to certain international human rights agreements are also exempt. But it effectively shuts out most asylum seekers and, on its own, represents the “most significant change in the modern asylum system since 1980,” Chishti said.

The Trump administration has also brokered agreements with Guatemala, Honduras, and El Salvador that could allow the US to return asylum seekers to those countries.

Outgoing Acting DHS Secretary Kevin McAleenan — who was a vocal supporter of increasing aid to Central America before he became acting secretary — has framed these agreements as a way to help the countries develop their asylum systems, including a pledge of $47 million to Guatemala for that purpose and a “commitment” to help build capacity in El Salvador.

But they also include provisions that could be used to require migrants on their way to the US to seek asylum and other protections in those countries first.

It’s not clear at this point whether these agreements would actually be used to deport large numbers of asylum seekers showing up at the US border.

Taken together, the Trump administration’s rule and its agreements with Central American countries can be used to block the overwhelming majority of asylum claims from migrants showing up at the border. The administration has not had to rely on those policies to deport asylum seekers just yet; Trump has made asylum inaccessible for most recent arrivals by other means. But if courts strike those efforts down, the administration may revert to using these policies as another buffer against asylum seekers.

2) Mexico has become the choke point

The journey through Mexico alone is dangerous. As many as half a million migrants annually hitch a ride through the country atop a network of freight trains, known as “La Bestia” or “The Beast,” for days or weeks.

Along the way, they are targeted by criminal gangs and frequently kidnapped. And under Trump, migrants have also had to contend with Mexican authorities.

Mexico has refused to sign a “safe third country” agreement, which would allow the US to turn away migrants who did not first seek asylum in Mexico. But it has started to cooperate with the Trump administration on immigration enforcement, stopping migrants in their tracks before they reach the US border.

Mexican President Andrés Manuel López Obrador promised upon assuming office in December 2018 not to do the US’s “dirty work” in solving the Central American migration crisis. He distanced himself from the harsh immigration enforcement policies of his predecessor Enrique Peña Nieto, who initiated an enforcement program in 2014 on Mexico’s southern border with Guatemala under which some 700,000 migrants were deported; instead, it sought to provide temporary humanitarian visas and work permits to migrants passing through Mexico.

But in June, Trump threatened to impose tariffs on all Mexican goods unless López Obrador agreed to drive down the number of migrants arriving at the US southern border. López Obrador did an about-face: He deployed a record 15,000 troops to detain over 31,000 migrants that month and almost 19,000 in July.

Mark Morgan, the acting CBP commissioner, has praised Mexico’s enforcement efforts, attributing the recent drop in border apprehensions at the US southern border to López Obrador’s administration.

“The partnership between Mexico and the United States concerning this regional crisis is having a dramatic impact,” he told reporters on October 8. “[T]he cooperation and partnership we have with Mexico right now really is one for the history books.”

Mexico has consequently created a bottleneck for asylum seekers. If detained and deported by Mexican authorities, they may never even be able to reach the US border in order to claim asylum.

3) Getting in line at the US-Mexico border doesn’t work anymore

If asylum seekers reach the southern border, they face a choice: either line up at a port of entry and wait to be processed by CBP officers, or try to cross the border without authorization. But the Trump administration has made waiting untenable.

Starting in mid-2018, CBP officials started limiting the number of asylum seekers they processed at ports of entry each day, forcing the others to wait in Mexico, where migrant shelters are at capacity and many have been forced to sleep on the streets.

Mexican immigration authorities keep lists of those who are waiting. The number of names on those lists exceeded 26,000 in August and there’s no telling how long much longer they will have to remain there before they are processed at the port.

An ongoing lawsuit brought by Al Otro Lado, one of the few legal aid organizations serving migrants in Mexico, argues that the metering policy deprives migrants of access to the US asylum system and is in violation of federal immigration law and their constitutional due process rights. Al Otro Lado has asked a federal court in California to block the policy, but in the meantime, it remains in effect.

There have also been numerous cases of families who were separated after finally being processed at ports of entry, even after a federal court prohibited the practice and despite DHS’s claims to the contrary.

That might make the prospect of crossing the border without authorization a more attractive option. Democratic presidential candidate Julián Castro has argued that it is what caused 25-year-old Oscar Alberto Martínez Ramírez to attempt to cross the Rio Grande with his 23-month-old daughter Valeria. They drowned; their bodies were discovered on June 24.

“This metering policy is basically what prompted Oscar and Valeria to make that risky swim across the river,” Castro said during the first Democratic primary debate in June. “Oscar and Valeria went to a port of entry, and then they were denied the ability to make an asylum claim, so they got frustrated and they tried to cross the river, and they died because of that.”

4) There is no guarantee of entry to the US

Even if asylum seekers finally get in front of an immigration agent, they won’t necessarily be allowed to enter the US.

Previously, both those who waited in line at the border and those who were apprehended between ports of entry would have been held at a CBP processing facility until a border agent determined whether they should be released, transferred to ICE detention, or deported. But now, most are quickly sent back to Mexico under the Trump administration’s “Remain in Mexico” policy, officially known as the “Migrant Protection Protocols” (MPP).

The policy, which was unveiled in January, applies to both those processed at ports of entry and those apprehended while trying to cross the border without authorization. It allows the government to send migrants with credible asylum claims back to Mexico while they await a final decision on their applications. About 55,000 migrants have been subject to the policy as of October, a CBP spokesperson told Vox. They have been allowed to enter the US only to attend their immigration court hearings, and largely unable to access legal counsel.

McAleenan announced in September that the policy now covers most families arriving at the southern border.

Under its own guidance, DHS is supposed to exempt “vulnerable populations” from the Remain in Mexico policy and allow them to stay in the US, but anecdotally, few migrants have been able to obtain such exemptions. A CBP spokesperson told Vox that the agency does not track the number of exemptions granted.

The advocacy group Human Rights First issued a report earlier this month documenting dozens of cases in which inherently vulnerable immigrants — including those with serious health issues and pregnant women — and immigrants who were already victims of kidnapping, rape, and assault in Mexico were sent back under MPP.

The Ninth Circuit, however, is considering a case challenging the policy and could block it any day now.

5) Trump has massively expanded the detention of asylum seekers

Immigration agents who process asylum seekers at the border — either after they stood in line at a port of entry or after they were caught trying to cross without authorization — will usually send them back to Mexico under the Remain in Mexico policy. But as an alternative, authorities can instead choose to detain them at facilities inside the US.

The Trump administration has done so systematically, setting out to indiscriminately prosecute and detain anyone who tries to cross the border without authorization, even if they ask for asylum, under its “zero tolerance” policy.

Announced in April 2018, the zero tolerance policy coincided with a shift in the demographics of migrants showing up at the border: Families now make up the majority of those apprehended, rather than single adult males.

As a result, the Trump administration has sent record numbers of asylum-seeking families to immigration detention who typically would have been released under previous administrations. The government’s rationale was that the practice of releasing families — what Trump has called “catch and release” — was encouraging migrants to come to the US and that keeping them in detention while their immigration cases were underway would deter further migration.

It’s not clear whether it’s been an effective deterrent. Even as the administration was filling detention centers to their capacity and obtaining additional funding for more beds in immigration detention, the number of migrants showing up at the border kept rising through April of this year. The overall numbers have since fallen, but for migrants who face genuine danger in their home countries, the change in detention policy isn’t likely to stop them from seeking refuge in the US.

The US does not have enough facilities licensed to detain families on the scale Trump has sought, which in part led his administration to separate over 4,000 immigrant families before a court ordered it to end the practice in July 2018. But the administration is still pursuing a rule that would allow it to put more families in detention and hold them indefinitely, eliminating certain restrictions on the detention of children. A federal court, however, has also blocked that effort for now.

Though the family separations crisis is mostly over, the conditions in detention centers remain substandard and dangerous. Since Trump took office, 12 immigrants have died in CBP custody and another 27 have died in ICE custody, including a 2-year-old suffering from pneumonia and a 7-year-old who went into cardiac arrest from severe dehydration.

Migrants aren’t supposed to be held in CBP facilities for more than 72 hours under the agency’s own guidelines. But CBP hasn’t complied with those guidelines following the implementation of the zero tolerance policy.

So migrants remain in dangerously overcrowded facilities that were never designed to hold them for days and weeks at a time, sleeping on concrete floors with nothing but mylar blankets. A federal appeals court ruled in August that CBP was obligated to provide basic hygiene items including toothbrushes and soap to children in its custody after a government attorney suggested that those items were nonessential. The conditions in many ICE detention facilities have been found to be similarly inhumane.

6) Asylum seekers aren’t getting a fair day in court

Usually while still detained, most migrants seeking asylum will have to make their case before an immigration judge in what is usually a lengthy process: As of June, migrants with active immigration cases have been waiting an average of almost two years for a decision.

Immigrants typically have a short initial hearing before a judge and a government attorney to learn about their rights and how their case will proceed. They are usually given time to retain a lawyer and prepare their case, which includes gathering documents attesting to experiences that might make them eligible for relief from deportation or protections under the asylum system or international torture agreements.

They then have to wait for another hearing in which they actually argue why they should be permitted to remain in the US before an immigration judge makes a decision on their case.

Immigration judges don’t operate in the federal court system — they’re overseen by the Department of Justice, the same agency that is currently trying to prosecute immigrants for crossing the border without authorization. While the DOJ has traditionally left the immigration courts to operate independently, Trump’s attorney generals have increasingly intervened, raising concerns that immigrants are being deprived of a fair day in court.

US Attorney General William Barr and his predecessor Jeff Sessions have tried to make it more difficult for victims of gang violence and domestic abuse, LGBTQ individuals, and those whose family members have been persecuted to obtain asylum.

They’ve also introduced policy changes that they claimed were designed to whittle down the backlog of cases in the immigration courts, which surpassed 1 million in August, but that have put migrants’ due process rights at risk.

Most significantly, Sessions established case completion quotas for immigration judges, encouraging them to quickly order immigrants deported and deny their asylum claims. Both Sessions and Barr have also taken away a number of tools that immigration judges have traditionally used to give asylum seekers more time to obtain attorneys or to close deportation cases that weren’t high priority.

All of these changes have sparked renewed support in the advocacy community to make the immigration court system independent of the DOJ.

DHS has also constructed temporary courts — which opened last month in tent complexes near CBP ports in Laredo and Brownsville, Texas, — to hear cases from migrants affected by Remain in Mexico. Immigrants and their attorneys video conference with judges and DHS attorneys appearing virtually, streamed from brick-and-mortar immigration courts hundreds of miles away.

House Democrats have called for investigations of the temporary courts, raising concerns that they violate migrants’ due process rights by restricting their access to attorneys and relying on teleconferencing. They also expressed alarm that the public has largely been barred from entering the tent facilities, shrouding their operations in secrecy.

7) Some migrants never set foot in a courtroom at all

The government has the power to put some migrants in what’s called “expedited removal proceedings,” under which they can be deported in a matter of days without seeing a judge or an attorney. It currently applies to individuals who are arrested within 100 miles of a land border within two weeks of their arrival.

But in July, Trump tried to expand who can be subjected to expedited removal, issuing a rule that would have also included immigrants found anywhere in the US if they arrived within the last two years — an estimated 20,000 people annually. That rule has been blocked temporarily as part of an ongoing legal challenge, but it could still be revived.

The administration also wants to make it much more difficult for asylum seekers to get work permits during the months or years it takes for their claims to make their way through court. For non-detained asylum seekers who cannot afford to be unemployed and are not eligible for most public benefits, that means they would need to either give up their asylum claims in the US altogether or find under-the-table jobs in the shadow economy.

These incremental, technical changes in the immigration court system collectively have put asylum seekers’ access to justice at risk. But now that most asylum seekers are being pushed back to Mexico and having their hearings at the secretive tent facilities on the border, the problem is nowhere near as visible to the public.

“I don’t think the public knows that the modern asylum system has been eroded because this has happened one thing at a time,” Chishti said. “There is a certain amount of fatigue in opposition to Trump. It’s very difficult to maintain the intensity.”