I hope the Trump administration is prepared to "push back".
If they try to enter at a border crossing, refuse them.
If they try to rush the border elsewhere, do whatever is necessary to drive them back.
If any still get through, round them up and don't even process them -- put them on transportation back south immediately.
If this involves injury -- to (even) women and children -- we'll have to accept that
They are invaders.
They should be repelled.
Addendum:
Back in the early '70's, Frenchman Jean Raspail wrote a book about what happens when a nation FAILS to resist and repel invasions like this.
It's named "The Camp of the Saints", and if you haven't read it, you should.
Or... for the "condensed version"... just look at Western Europe today...