Some of this ugly and stupid behavior is the pleasure in power of petty tyrants in their little bureaucratic realm, otherwise powerless individuals who now find others at their mercy and whim. But it is surely exacerbated by the signals sent by the Idiot in Chief. One important takeaway: academics on tourist visas in the U.S. can receive honoraria. (Thanks to Benj Helli for one of the pointers.)
I'd be curious to hear what experiences readers may have had coming into the U.S. since Trump took office and began his immigration rampage.