There is much lamenting in Europe over Donald Trump’s decision to end the U.S. leadership on trade liberalization, mostly because it exposes Europe’s limited ability to fill the void. Mexico Miscalculates Mexico’s President Enrique Pena Nieto cannot win for losing. The decision to cancel his meeting with U.S. President Donald Trump reflects the truly weak position of his country, the weakness of his personal character or perhaps both. Mr. Pena Nieto took a drubbing at home and in the media when he last met candidate Trump, largely because his advisors had not figured out how to play the American egotist. Trump is not ridiculing Japan, despite its many decades of trade surpluses with America, and he isn’t talking about building a wall alon...