Stop the negligence and horrible conditions ? In my opinion sadly either him getting voted out or some sort of court thing .
Abuse sadly often is a slope and it gets really bad before people step in (courts/media coverage).
A concerted constant effort of congress visiting and inspecting might help .
If he wins it's going to take worse because he'll keep up the current conditions saying he has a mandate for what he's doing . They've essentially laid out that if you come we're going to put you in these centers and until you return and a significant part of the country is willing to turn a blind eye to it .
What solutions are there ? There can be some such as increasing asylum I nflow at legal ports drastically while allowing stricter rules on illegal (dems win on humanitarian republicans win on law and order and it negates their do it legal argument) . Some on this very forum will find this anathema they will argue anyone should be let in . That becomes a very hard position to defend in sort of any meaningful policy in today's world . Also something like that being considered is an issue as the parties and sides are too entrenched for now ... trump doesn't help one bit of course .
Having said that willful murder/extermination/ethnic cleaning are words I definitely would not use as some in this thread are doing .
I look at this as a problem with potency far beyond Trump to be honest. At some point, either next year or in 2024, he will no longer be President.
However the political vision he's laid out here won't go away. His comments this past weekend have been enormously popular with Republican voters, and the party. They've really been building for decades, and don't show any sign of going away even if he's defeated.
Which is why I get very worried, the ideological and a lot of the structural framework work for detaining and abusing people is already in place. The overton window in conservative American politics is no longer simply there needs to be a process for dealing with undocumented or "illegal" immigrants, but now it's about how birthright citizenship needs to be ended, and how people of colour who criticise America should get out, even if their families have been US citizens for generations.
If climate change isn't combated in any meaningful way, the tension is only going to get heightened. Rising sea levels will increase the competition for resources and arable land both between the US and Central and South America, and within the US itself.
Already a pretty unequal country in terms of wealth, it's not hard to imagine future authoritarians using these crisis to justify going even further, and it's not hard to imagine who they'll pick first to target.