Trump let May have it. Her soft Brexit, her plans for a deal with Europe that would keep the British economy from being severely punished by European tariffs, are unacceptable to Trump and his circle. Their mouths had been watering at the thought of being able to go into Britain without all those pesky EU regulations and to wring profits out of its economy by firing workers ("downsizing"), or by razing environmental regulations so as to profit from poisoning the earth, or by buying up thriving firms and selling off their parts at a profit, destroying them but making a huge killing. If May does soft Brexit, the EU regulations interfering with Barracuda Capitalism will still be in place and Trump and his buddies won't be able to prey on the UK in the same way.
So in the interview, he let May have it, and went over her head to appeal to the British far right, which May had unwisely attempted to accommodate in her Tory party.
Having bloodied her quite publicly, having threatened her and slapped her around, Trump then met with her in public and put the illusion of honor back in place. The special relationship is the most special. Theresa May is the best thing since sliced (white) bread. The interview was "fake news."
Because in the world of organized crime, as in literary deconstruction, you have to hold opposites in tension with one another to produce meaning.
Mind you, Theresa May is a horrible person who has no respect for the rule of law or for people's privacy and who is tempted by some of the worst tropes of the British Right, and so it is hard to feel any sympathy for her as she is mauled by Trump as though she were trapped sitting next to him on a plane.
She has a choice, now, of standing up for herself or of being maneuvered by Trump into being his gun moll.
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Bonus video:
Trump in UK: Protests in Central London -- BBC News
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