By Learning to become a spy is hard. It's really hard. You've got to work on your extremely serious face and remember not to wave at your spy mates in the pub and give the game away: there's a lot of potential trip hazards.
But some aspects of international discretion and tact are within everyone's reach. Somewhere toward the front of the Dorling Kindersley kids' book on How To Be A Spy, between the section on making invisible ink out of lemon juice and making a secret hotline out of tin cans and string, there's a bit which says very clearly: if you have a piece of paper with secret information on it, don't wave it around in front of a pack of photographers.
Paper, it transpires, is not quite the impenetrable forcefield Donald Trump assumed it was. Some of the details of his agreement with Mexico over border security - which Trump declined to chat to reporters about because it was "secret" - were fairly easily deciphered.
It suggests that Mexico has agreed to a deadline when it would have to show that it had made some progress in slowing the movement of people from countries in Central and South America through Mexico to the United States. Presumably Trump's unlikely to have the CIA pressing him to get on its grad scheme once he's through with his time in office.
Like this article? Sign up to our newsletter to get more articles like this delivered straight to your inbox
