>>FWIW, I still don't know why Trump considers the "caravan" an invasion, other than because he says so.
What's your definition of invasion? Not the military definition, there are at least 2 other dictionary definitions in common parlance.
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1