It has long been obvious that migrants in the custody of the US Border Patrol were being detained in horrendous conditions. But not many cared to look, and congresswoman Alexandria Ocasio-Cortez was mocked when she claimed that “concentration camps” were being run along the border. In the past few days, however, a series of exposures has demonstrated that extreme language is more than justified.

First, Ocasio-Cortez and a congressional delegation visited two detention facilities in Texas, where they found detainees who hadn’t bathed in weeks, were sleeping on concrete floors and had limited access to drinking water. Ocasio-Cortez met with women crying “out of fear of being punished, out of sickness, out of desperation, lack of sleep, trauma, despair”. She said women had been encouraged to drink out of toilet bowls and that Border Patrol agents were laughing about the situation in front of the delegation.

Ocasio-Cortez’s statements were pounced on by conservatives, who accused her of exaggerating conditions. Rush Limbaugh said she had made “baseless charges” and was pulling a “stunt”. Immigration officials accused her of misinforming the public. But documents released this week by the Department of Homeland Security (DHS) inspector general were if anything even more disturbing. She found “dangerous overcrowding” in “cells designed for about one-fifth as many detainees”, and that “children at three of the five border patrol facilities we visited had no access to showers”.

Inspectors said the cells “smelled of what might have been unwashed bodies/body odour, urine, untreated diarrhea, and/or soiled clothing/diapers”, had no room to lie down and were at a temperature of over 80F (27C). At one facility adults were held in standing-room-only conditions for a week, and detainees’ personal property was “discarded in a dumpster behind the station”. The reports were accompanied by shocking photos.

Then there were the Facebook posts. A ProPublica investigation reported a closed Facebook group for current and former Border Patrol agents engaging in sexist and xenophobic language, photoshopping Ocasio-Cortez into scenes of sexual assault, joking about putting migrant children in trash bags and responding “with indifference and wisecracks” to stories of migrants who had died in custody. It would not be surprising that an agency charged with a fundamentally dehumanising mission would have a dehumanising internal culture, but ProPublica’s reporting seemed to demonstrate the kind of callous indifference to human life that is normalised among agents.

None of this is new – demeaning and unsanitary conditions in border cells were well-documented during the Obama administration. But no one should have tolerated their government keeping people locked up like this back then and they shouldn’t tolerate it now. As the slogan goes: “If you’re not outraged, you’re not paying attention.”

‘The DHS will try to convince people that the problem is a lack of adequate facilities in which to detain people rather than the overuse of detention itself.’ Women held in a detention centre in Texas. Photograph: AFP/Getty Images

It’s important, however, to be clear about both what is going on and what ought to be done about it. The DHS has been crying out that it is “under-resourced” and thus unable to release people swiftly from these border cells, which are intended to be used for a maximum of only three days. It will try to use the public’s outrage over conditions in the cells to make other forms of longer-term detention – in family detention centres and immigration jails – seem like humane alternatives.

The DHS has already attempted to blame the long waits in short-term Border Patrol facilities on the fact there are not enough beds in the longer-term Immigration and Customs Enforcement (ICE) facilities. That’s almost certainly a disingenuous justification because there’s evidence ICE isn’t nearly as overstretched as it claims. (The largest family detention centre has consistently had hundreds of empty beds this year.) But by talking about this as a resources issue, the DHS will try to convince people that the problem is a lack of adequate facilities in which to detain people rather than the overuse of detention itself. With poor oversight of Border Patrol operations, increasingly prolonged detention periods for migrants will become normalised, leading to people being tortured for weeks instead of days, and then months instead of weeks.

The Trump administration doesn’t necessarily mind people pointing out that conditions are squalid and appalling. Why? Because that helps it make the case for building more jails. Democrats can very easily fall into the trap of making the right’s own argument for it. We say: “Look at these horrible overcrowded border cells.” They reply: “Yes, how awful, that’s why we need bigger detention facilities where people can be held for longer.” And Democrats agree to a giant new funding package for border enforcement.

Facebook Twitter Pinterest ‘The Trump administration doesn’t necessarily mind people pointing out that conditions are squalid and appalling.’ Men detained at a border patrol station in McAllen, Texas. Photograph: Office Of Inspector General Handout/EPA

People who are detained need to be detained humanely, with access to soft beds, good food, soap, showers, leisure. That should go without saying. But “detain people humanely” is a pitifully inadequate rallying cry for those who care about migrant rights. The past decade has seen the growth of a vast system of detention that never existed before. The presumption that migrants must be jailed is becoming increasingly entrenched, despite the fact that border crossing numbers were higher in the mid-2000s than they are now, and despite a total lack of evidence that immigrants pose any danger to the rest of the public.

It’s also worth pointing out that some other ways to reduce operational strain on the border will also make the situation far worse for migrants. For example, the Trump administration has recently been expanding its new “Remain in Mexico” programme. Under this policy asylum-seekers are forced to remain in dangerous Mexican border towns rather than being allowed entry to the US. Keeping asylum-seekers from coming in the first place is certainly one way to reduce the number in custody, but it doesn’t make their lives any better.

Ocasio-Cortez details 'horrifying' conditions at migrant detention facility Read more

Always be clear on what the problem is: it’s that large numbers of people who should be entitled to seek a decent life in the US, the way generations have before, are being turned back or caged. Once they are here they are at risk of having their lives torn apart and their families taken from them. The progressive position is not to jail people in slightly better conditions, but free them.

Detained people need rights, but, more importantly, we must argue that detention needs to be a minimal part of any US immigration policy. The more people we keep caged, and the longer we keep them there, the closer we come to adopting a permanent network of what can fairly be described as concentration camps.

• Brianna Rennix works in immigration law. Nathan Robinson is editor of Current Affairs