He has codified massive funding to ICE in the BBB, which he has direct control over.

So he can order people to be detained and deported, knowing that the legal system can't handle the appeals of that many people.

Furthermore, the only way he will leave office is if his disease gets bad enough to where he can't function. And then the assumption is that the crazies he has hired aren't going to basically take over the government completely. If he is able to function in 2026 and 2028, US won't have real elections.