Whether Donald Trump lied about discussing who would pay for the border wall during his meeting Wednesday with Mexican President Peña Nieto is immaterial. The most important takeaway here is that Donald Trump is an international incident waiting to happen.
You can't malign an entire people, say they're responsible for ruining your country, tell them that they must be physically blockaded from entry, then go to their nation and expect things to go well.
But somehow, beyond all reasonability, Donald Trump and his team decided that, yes, yes, you could do that. You could visit the country of the people you had derided and taunted and jeered. Call it idiocy or blind optimism or perhaps Trump exceptionalism—call it what you will, but it was a fantastical alternate universe Team Trump was taking for a spin when they smashed headlong into the reality that anchors the rest of us to this planet.
Everyone with a lick of sense knew Trump's Mexico trip would blow up. It wasn't clear how, but it was an inevitability. Well, it has. And rest assured, international incidents where something goes terribly wrong would be a hallmark of a Trump presidency, not an aberration.