There are trade agreements that are negotiated at diplomatic tables and others that, without being written, are negotiated every day on the basis of trust.The T-MEC belongs to both categories.That's why, reducing its review to a discussion on tariffs, rules of origin or trade deficits is to keep just part of the story.The decision of the Donald Trump administration to tighten the scrutiny of the agreement responds, of course, to a more protectio…