He'd set up a temporary camp for them while they are processed through the legal system. Greet them with lawyers, process a couple dozen cases a day. If they have a good case for asylum, they can stay. Otherwise, out they go.
The "caravan" Trump wants us to be so afraid of is half the size it once was. By the time it reaches our shores (maybe January), it will be tiny.
Last time a "caravan" came, 14 people made it the whole way.
Some crisis.
Trump thinks you are a total fucking moron. If you fear the caravan, you prove him right.