I think it is easy to underestimate the ugliness and disorder such a reckless executive order can unleash unless you start to think about the details or put yourself in the shoes of the people affected.
NBC News reports[0]:
The Trump administration also has yet to issue guidance to airports and airlines on how to implement the executive order. "Nobody has any idea what is going on," a senior Homeland Security official told NBC News.
As James Gleick put it on Twitter[1]:
And how was it communicated to Customs and Border Protection? Or have they just gone rogue?
And then there is the gross conflict-of-interest reflected in this map:
https://www.bloomberg.com/graphics/2017-trump-immigration-ba...
The event marks a horrible landmark. It's the first time I can point to the tangible harmful impact of Trump's executive policy on actual people. Up to this point, it has been possible for supporters and apologists to waive away his vague or careless remarks during the campaign as political rhetoric, jokes, or leverage for future negotiation. Now we start to see the mean (in every sense of the word) instinct that informed them and the harm they can do.
[0] http://www.nbcnews.com/news/world/trump-travel-restrictions-...
[1] https://twitter.com/JamesGleick/status/825380079526146048